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54-562: Chatsworth Calera also called Chatsworth Reservoir Kiln Site is one of the few surviving structures of the early 1800s lime industry. This kiln marked the introduction to California of the European industrial process for vitrifying limestone building blocks which were used in the construction of the San Fernando mission and other mission buildings. The word "Calera" is Spanish for "limestone quarry" or "limekiln". Chatsworth Calera

108-432: A mass-production basis, which limited them to a number of specialised applications. The MOSFET was invented at Bell Labs between 1955 and 1960. It was the first truly compact transistor that could be miniaturised and mass-produced for a wide range of uses. Its advantages include high scalability , affordability, low power consumption, and high density . It revolutionized the electronics industry , becoming

162-403: A radio antenna , practicable. Vacuum tubes (thermionic valves) were the first active electronic components which controlled current flow by influencing the flow of individual electrons , and enabled the construction of equipment that used current amplification and rectification to give us radio , television , radar , long-distance telephony and much more. The early growth of electronics

216-428: A tunnel kiln , is long with only the central portion directly heated. From the cool entrance, ware is slowly moved through the kiln, and its temperature is increased steadily as it approaches the central, hottest part of the kiln. As it continues through the kiln, the temperature is reduced until the ware exits the kiln nearly at room temperature. A continuous kiln is energy-efficient, because heat given off during cooling

270-460: A key factor in the development of Chinese pottery , and until recent centuries was the most advanced in the world. The Chinese developed kilns capable of firing at around 1,000 °C before 2000 BCE . These were updraft kilns, often built below ground. Two main types of kiln were developed by about 200 AD and remained in use until modern times. These are the dragon kiln of hilly southern China , usually fuelled by wood, long and thin and running up

324-418: A leading role in the field of microwave and high power transmission as well as television receivers until the middle of the 1980s. Since then, solid-state devices have all but completely taken over. Vacuum tubes are still used in some specialist applications such as high power RF amplifiers , cathode-ray tubes , specialist audio equipment, guitar amplifiers and some microwave devices . In April 1955,

378-566: A mix of the two types. Analog circuits are becoming less common, as many of their functions are being digitized. Analog circuits use a continuous range of voltage or current for signal processing, as opposed to the discrete levels used in digital circuits. Analog circuits were common throughout an electronic device in the early years in devices such as radio receivers and transmitters. Analog electronic computers were valuable for solving problems with continuous variables until digital processing advanced. As semiconductor technology developed, many of

432-540: A physical space, although in more recent years the trend has been towards electronics lab simulation software , such as CircuitLogix , Multisim , and PSpice . Today's electronics engineers have the ability to design circuits using premanufactured building blocks such as power supplies , semiconductors (i.e. semiconductor devices, such as transistors), and integrated circuits. Electronic design automation software programs include schematic capture programs and printed circuit board design programs. Popular names in

486-530: A range of firing conditions. Both Ancient Roman pottery and medieval Chinese pottery could be fired in industrial quantities, with tens of thousands of pieces in a single firing. Early examples of simpler kilns found in Britain include those that made roof-tiles during the Roman occupation. These kilns were built up the side of a slope, such that a fire could be lit at the bottom and the heat would rise up into

540-418: A slope, and the horseshoe-shaped mantou kiln of the north Chinese plains, smaller and more compact. Both could reliably produce the temperatures of up to 1300 °C or more needed for porcelain . In the late Ming, the egg-shaped kiln or zhenyao was developed at Jingdezhen and mainly used there. This was something of a compromise between the other types, and offered locations in the firing chamber with

594-548: Is defined as unwanted disturbances superposed on a useful signal that tend to obscure its information content. Noise is not the same as signal distortion caused by a circuit. Noise is associated with all electronic circuits. Noise may be electromagnetically or thermally generated, which can be decreased by lowering the operating temperature of the circuit. Other types of noise, such as shot noise cannot be removed as they are due to limitations in physical properties. Many different methods of connecting components have been used over

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648-506: Is especially true in the drying of thin veneers and high-temperature drying of softwoods. Electronics Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other electrically charged particles . It is a subfield of physics and electrical engineering which uses active devices such as transistors , diodes , and integrated circuits to control and amplify

702-687: Is now located in Chatsworth, Los Angeles , California . in the Chatsworth Nature Preserve . At its peak there may have been up to five kilns at the site run by native Indian laborers. Chatsworth Calera registered a California Historical Landmark No. 911. The Chatsworth Calera is also a Los Angeles Historic-Cultural Monument #141, thus designated on April 2, 1975, by the Los Angeles Cultural Heritage Commission. The Chatsworth Calera kiln

756-444: Is often provided early in the schedule to supplement the dehumidifier. Solar kilns are conventional kilns, typically built by hobbyists to keep initial investment costs low. Heat is provided via solar radiation, while internal air circulation is typically passive. Vacuum and radio frequency kilns reduce the air pressure to attempt to speed up the drying process. A variety of these vacuum technologies exist, varying primarily in

810-404: Is recycled to pre-heat the incoming ware. In some designs, the ware is left in one place, while the heating zone moves across it. Kilns in this type include: In the intermittent kiln , the ware is placed inside the kiln, the kiln is closed, and the internal temperature is increased according to a schedule. After the firing is completed, both the kiln and the ware are cooled. The ware is removed,

864-416: Is removed by a system of vents, the specific layout of which are usually particular to a given manufacturer. In general, cool dry air is introduced at one end of the kiln while warm moist air is expelled at the other. Hardwood conventional kilns also require the introduction of humidity via either steam spray or cold water misting systems to keep the relative humidity inside the kiln from dropping too low during

918-595: Is the voltage comparator which receives a continuous range of voltage but only outputs one of two levels as in a digital circuit. Similarly, an overdriven transistor amplifier can take on the characteristics of a controlled switch , having essentially two levels of output. Analog circuits are still widely used for signal amplification, such as in the entertainment industry, and conditioning signals from analog sensors, such as in industrial measurement and control. Digital circuits are electric circuits based on discrete voltage levels. Digital circuits use Boolean algebra and are

972-448: Is therefore the process of defining and developing complex electronic devices to satisfy specified requirements of the user. Due to the complex nature of electronics theory, laboratory experimentation is an important part of the development of electronic devices. These experiments are used to test or verify the engineer's design and detect errors. Historically, electronics labs have consisted of electronics devices and equipment located in

1026-540: The City of Los Angeles , . She learned about the kiln from Max Knapp a Chatsworth valley pioneer stonemason. William Warren Orcutt a geologist and paleontologist wrote about the limestone outcrops near his ranch Rancho Sombra del Roble. He believed these outcrops to be of especially good quality for lime production. Two mile south of Chatsworth Calera is the Dayton Canyon Kilns. Kiln According to

1080-624: The IBM 608 was the first IBM product to use transistor circuits without any vacuum tubes and is believed to be the first all-transistorized calculator to be manufactured for the commercial market. The 608 contained more than 3,000 germanium transistors. Thomas J. Watson Jr. ordered all future IBM products to use transistors in their design. From that time on transistors were almost exclusively used for computer logic circuits and peripheral devices. However, early junction transistors were relatively bulky devices that were difficult to manufacture on

1134-841: The Oxford English Dictionary , kiln was derived from the words cyline, cylene, cyln(e) in Old English , in turn derived from Latin culina ("kitchen"). In Middle English , the word is attested as kulne, kyllne, kilne, kiln, kylle, kyll, kil, kill, keele, kiele. In Greek the word καίειν, kaiein , means 'to burn'. The word "kiln" was originally pronounced "kil" with the "n" silent, as is referenced in Webster's Dictionary of 1828 and in English Words as Spoken and Written for Upper Grades by James A. Bowen 1900: "The digraph ln, n silent, occurs in kiln. A fall down

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1188-459: The electron in 1897 by Sir Joseph John Thomson , along with the subsequent invention of the vacuum tube which could amplify and rectify small electrical signals , inaugurated the field of electronics and the electron age. Practical applications started with the invention of the diode by Ambrose Fleming and the triode by Lee De Forest in the early 1900s, which made the detection of small electrical voltages, such as radio signals from

1242-448: The 1960s, U.S. manufacturers were unable to compete with Japanese companies such as Sony and Hitachi who could produce high-quality goods at lower prices. By the 1980s, however, U.S. manufacturers became the world leaders in semiconductor development and assembly. However, during the 1990s and subsequently, the industry shifted overwhelmingly to East Asia (a process begun with the initial movement of microchip mass-production there in

1296-538: The 1970s), as plentiful, cheap labor, and increasing technological sophistication, became widely available there. Over three decades, the United States' global share of semiconductor manufacturing capacity fell, from 37% in 1990, to 12% in 2022. America's pre-eminent semiconductor manufacturer, Intel Corporation , fell far behind its subcontractor Taiwan Semiconductor Manufacturing Company (TSMC) in manufacturing technology. By that time, Taiwan had become

1350-712: The EDA software world are NI Multisim, Cadence ( ORCAD ), EAGLE PCB and Schematic, Mentor (PADS PCB and LOGIC Schematic), Altium (Protel), LabCentre Electronics (Proteus), gEDA , KiCad and many others. Heat generated by electronic circuitry must be dissipated to prevent immediate failure and improve long term reliability. Heat dissipation is mostly achieved by passive conduction/convection. Means to achieve greater dissipation include heat sinks and fans for air cooling, and other forms of computer cooling such as water cooling . These techniques use convection , conduction , and radiation of heat energy . Electronic noise

1404-535: The advancement of electronics is the semiconductor industry , which in response to global demand continually produces ever-more sophisticated electronic devices and circuits. The semiconductor industry is one of the largest and most profitable sectors in the global economy, with annual revenues exceeding $ 481 billion in 2018. The electronics industry also encompasses other sectors that rely on electronic devices and systems, such as e-commerce, which generated over $ 29 trillion in online sales in 2017. The identification of

1458-548: The air in the chamber is then heated and finally a vacuum is pulled as the charge cools. SSV run at partial-atmospheres, typically around 1/3 of full atmospheric pressure, in a hybrid of vacuum and conventional kiln technology (SSV kilns are significantly more popular in Europe where the locally harvested wood is easier to dry than the North American woods.) RF/V (radio frequency + vacuum) kilns use microwave radiation to heat

1512-409: The basis of all digital computers and microprocessor devices. They range from simple logic gates to large integrated circuits, employing millions of such gates. Digital circuits use a binary system with two voltage levels labelled "0" and "1" to indicated logical status. Often logic "0" will be a lower voltage and referred to as "Low" while logic "1" is referred to as "High". However, some systems use

1566-459: The circuit, thus slowing the computer. The invention of the integrated circuit by Jack Kilby and Robert Noyce solved this problem by making all the components and the chip out of the same block (monolith) of semiconductor material. The circuits could be made smaller, and the manufacturing process could be automated. This led to the idea of integrating all components on a single-crystal silicon wafer, which led to small-scale integration (SSI) in

1620-465: The clay until the particles partially melt and flow together, creating a strong, single mass, composed of a glassy phase interspersed with pores and crystalline material. Through firing, the pores are reduced in size, causing the material to shrink slightly. In the broadest terms, there are two types of kilns: intermittent and continuous, both being an insulated box with a controlled inner temperature and atmosphere. A continuous kiln , sometimes called

1674-437: The differential impact of the presence of drying equipment in a specific plant. Every piece of equipment from the green trimmer to the infeed system at the planer mill is part of the "drying system". The true costs of the drying system can only be determined when comparing the total plant costs and risks with and without drying. Kiln dried firewood was pioneered during the 1980s, and was later adopted extensively in Europe due to

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1728-581: The drying cycle. Fan directions are typically reversed periodically to ensure even drying of larger kiln charges. Most softwood kilns operate below 115 °C (239 °F) temperature. Hardwood kiln drying schedules typically keep the dry bulb temperature below 80 °C (176 °F). Difficult-to-dry species might not exceed 60 °C (140 °F). Dehumidification kilns are similar to other kilns in basic construction and drying times are usually comparable. Heat comes primarily from an integral dehumidification unit that also removes humidity. Auxiliary heat

1782-874: The early 1960s, and then medium-scale integration (MSI) in the late 1960s, followed by VLSI . In 2008, billion-transistor processors became commercially available. An electronic component is any component in an electronic system either active or passive. Components are connected together, usually by being soldered to a printed circuit board (PCB), to create an electronic circuit with a particular function. Components may be packaged singly, or in more complex groups as integrated circuits . Passive electronic components are capacitors , inductors , resistors , whilst active components are such as semiconductor devices; transistors and thyristors , which control current flow at electron level. Electronic circuit functions can be divided into two function groups: analog and digital. A particular device may consist of circuitry that has either or

1836-429: The economic and practical benefits of selling wood with a lower moisture content (with optimal moisture levels of under 20% being much easier to achieve). The total (harmful) air emissions produced by wood kilns, including their heat source, can be significant. Typically, the higher the temperature at which the kiln operates, the larger the quantity of emissions that are produced (per mass unit of water removed). This

1890-452: The electronic logic gates to generate binary states. Highly integrated devices: Electronic systems design deals with the multi-disciplinary design issues of complex electronic devices and systems, such as mobile phones and computers . The subject covers a broad spectrum, from the design and development of an electronic system ( new product development ) to assuring its proper function, service life and disposal . Electronic systems design

1944-404: The flow of electric current and to convert it from one form to another, such as from alternating current (AC) to direct current (DC) or from analog signals to digital signals. Electronic devices have hugely influenced the development of many aspects of modern society, such as telecommunications , entertainment, education, health care, industry, and security. The main driving force behind

1998-562: The following ways: The electronics industry consists of various sectors. The central driving force behind the entire electronics industry is the semiconductor industry sector, which has annual sales of over $ 481 billion as of 2018. The largest industry sector is e-commerce , which generated over $ 29 trillion in 2017. The most widely manufactured electronic device is the metal-oxide-semiconductor field-effect transistor (MOSFET), with an estimated 13   sextillion MOSFETs having been manufactured between 1960 and 2018. In

2052-489: The functions of analog circuits were taken over by digital circuits, and modern circuits that are entirely analog are less common; their functions being replaced by hybrid approach which, for instance, uses analog circuits at the front end of a device receiving an analog signal, and then use digital processing using microprocessor techniques thereafter. Sometimes it may be difficult to classify some circuits that have elements of both linear and non-linear operation. An example

2106-464: The kiln can kill you." Bowen was noting that "kill" and "kiln" are homophones . Pit fired pottery was produced for thousands of years before the earliest known kiln, which dates to around 6000 BCE , and was found at the Yarim Tepe site in modern Iraq . Neolithic kilns were able to produce temperatures greater than 900 °C (1652 °F). Uses include: Kilns are an essential part of

2160-431: The kiln charge, and typically have the highest operating cost due to the heat of vaporization being provided by electricity rather than local fossil fuel or waste wood sources. The economics of different wood drying technologies are based on the total energy, capital, insurance/risk, environmental impacts, labor, maintenance, and product degradation costs. These costs, which can be a significant part of plant costs, involve

2214-464: The kiln is cleaned and the next cycle begins. Kilns in this type include: Kiln technology is very old. Kilns developed from a simple earthen trench filled with pots and fuel pit firing , to modern methods. One improvement was to build a firing chamber around pots with baffles and a stoking hole. This conserved heat. A chimney stack improved the air flow or draw of the kiln, thus burning the fuel more completely. Chinese kiln technology has always been

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2268-411: The kiln. Traditional kilns include: With the industrial age , kilns were designed to use electricity and more refined fuels, including natural gas and propane . Many large industrial pottery kilns use natural gas, as it is generally clean, efficient and easy to control. Modern kilns can be fitted with computerized controls allowing for fine adjustments during the firing. A user may choose to control

2322-517: The kiln. Most softwood kilns are track types in which the timber is loaded on kiln/track cars for loading the kiln. Modern high-temperature, high-air-velocity conventional kilns can typically dry 1-inch-thick (25 mm) green wood in 10 hours down to a moisture content of 18%. However, 1-inch-thick green red oak requires about 28 days to dry down to a moisture content of 8%. Heat is typically introduced via steam running through fin/tube heat exchangers controlled by on/off pneumatic valves. Humidity

2376-435: The manufacture of almost all types of ceramics . Ceramics require high temperatures so chemical and physical reactions will occur to permanently alter the unfired body. In the case of pottery, clay materials are shaped, dried and then fired in a kiln. The final characteristics are determined by the composition and preparation of the clay body and the temperature at which it is fired. After a first firing, glazes may be used and

2430-399: The method heat is introduced into the wood charge. Hot water platten vacuum kilns use aluminum heating plates with the water circulating within as the heat source, and typically operate at significantly reduced absolute pressure. Discontinuous and SSV (super-heated steam) use atmosphere pressure to introduce heat into the kiln charge. The entire kiln charge comes up to full atmospheric pressure,

2484-434: The moisture content is between 18% and 8%. This can be a long process unless accelerated by use of a kiln. A variety of kiln technologies exist today: conventional, dehumidification, solar, vacuum and radio frequency. Conventional wood dry kilns are either package-type (side-loader) or track-type (tram) construction. Most hardwood lumber kilns are side-loader kilns in which fork trucks are used to load lumber packages into

2538-399: The most widely used electronic device in the world. The MOSFET is the basic element in most modern electronic equipment. As the complexity of circuits grew, problems arose. One problem was the size of the circuit. A complex circuit like a computer was dependent on speed. If the components were large, the wires interconnecting them must be long. The electric signals took time to go through

2592-478: The rate of temperature climb or ramp , hold or soak the temperature at any given point, or control the rate of cooling. Both electric and gas kilns are common for smaller scale production in industry and craft, handmade and sculptural work. Modern kilns include: Green wood coming straight from the felled tree has far too high a moisture content to be commercially useful and will rot, warp and split. Both hardwoods and softwood must be left to dry out until

2646-540: The reverse definition ("0" is "High") or are current based. Quite often the logic designer may reverse these definitions from one circuit to the next as they see fit to facilitate their design. The definition of the levels as "0" or "1" is arbitrary. Ternary (with three states) logic has been studied, and some prototype computers made, but have not gained any significant practical acceptance. Universally, Computers and Digital signal processors are constructed with digital circuits using Transistors such as MOSFETs in

2700-466: The ware is fired a second time to fuse the glaze into the body. A third firing at a lower temperature may be required to fix overglaze decoration. Modern kilns often have sophisticated electronic control systems, although pyrometric devices are often also used. Clay consists of fine-grained particles that are relatively weak and porous. Clay is combined with other minerals to create a workable clay body. The firing process includes sintering . This heats

2754-762: The years. For instance, early electronics often used point to point wiring with components attached to wooden breadboards to construct circuits. Cordwood construction and wire wrap were other methods used. Most modern day electronics now use printed circuit boards made of materials such as FR4 , or the cheaper (and less hard-wearing) Synthetic Resin Bonded Paper ( SRBP , also known as Paxoline/Paxolin (trade marks) and FR2) – characterised by its brown colour. Health and environmental concerns associated with electronics assembly have gained increased attention in recent years, especially for products destined to go to European markets. Electrical components are generally mounted in

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2808-653: Was ideal for kiln operation. Several lime kilns were in operation around the edge of the San Fernando Valley in the past. The Location is near the intersection of Woolsey Canyon Road and Valley Circle Blvd in Chatsworth about 9022 Valley Circle Blvd, Chatsworth, CA 91311. The kiln can be seen today looking east at the intersection. The ruins of the Chatsworth Calera came to public attention by environmental quality commissioner, Helen Treend, for

2862-473: Was rapid, and by the 1920s, commercial radio broadcasting and telecommunications were becoming widespread and electronic amplifiers were being used in such diverse applications as long-distance telephony and the music recording industry. The next big technological step took several decades to appear, when the first working point-contact transistor was invented by John Bardeen and Walter Houser Brattain at Bell Labs in 1947. However, vacuum tubes played

2916-455: Was used for burning limestone in the making of lime for concrete , mortar , and whitewash , a step in the construction of bricks and tiles. The monument site now looks like a hole in the ground with walls of vitrified limestone and brick. The pit measures about fifteen feet deep and six and a half feet across. The kiln was in use during early California history (Spanish/Mission and Mexican periods). The area rich with oak trees and lime deposits

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