Instruct: Given a question, retrieve documents that answer the question.
Query: How much did the first microwave oven cost?
In 1947, Raytheon built the "Radarange", the first commercially available microwave oven. It was almost tall, weighed and cost about US$5,000 ($ in dollars) each. It consumed 3 kilowatts, about three times as much as today's microwave ovens, and was water-cooled. The name was the winning entry in an employee contest. An early Radarange was installed (and remains) in the galley of the nuclear-powered passenger/cargo ship NS "Savannah". An early commercial model introduced in 1954 consumed 1.6 kilowatts and sold for US$2,000 to US$3,000 ($ to $ in dollars). Raytheon licensed its technology to the Tappan Stove company of Mansfield, Ohio in 1952. They tried to market a large 220 volt wall unit as a home microwave oven in 1955 for a price of US$1,295 ($ in dollars), but it did not sell well.
The development of radar, mainly in secrecy, before and during World War 2, resulted in the technological advances which made microwaves practical. Radar antennas small enough to fit on aircraft which had a narrow enough beamwidth to localize enemy aircraft required wavelengths in the centimeter range. It was found that conventional transmission lines used to carry radio waves had excessive power losses at microwave frequencies, and George Southworth at Bell Labs and Wilmer Barrow at MIT independently invented waveguide in 1936. Barrow invented the horn antenna in 1938 as a means to efficiently radiate microwaves into or out of a waveguide. In a microwave receiver, a nonlinear component was needed that would act as a detector and mixer at these frequencies, as vacuum tubes had too much capacitance. To fill this need researchers resurrected an obsolete technology, the point contact crystal detector (cat whisker detector) which was used as a demodulator in crystal radios around the turn of the century before vacuum tube receivers. The low capacitance of semiconductor junctions allowed them to function at microwave frequencies. The first modern silicon and germanium diodes were developed as microwave detectors in the 1930s, and the principles of semiconductor physics learned during their development led to semiconductor electronics after the war.
In 1947, the company produced the first commercial upright freezer. Two years later, the Amana Society sold off the Electrical Department to an investment group organized by Foerstner. Renamed Amana Refrigeration, Inc., the company grew to manufacture refrigerators and air conditioners. The Raytheon Corporation purchased Amana Refrigeration on January 1, 1965, although the Amana division was mostly autonomous. Amana produced the first practical commercial microwave oven in 1967. The division was sold to Goodman Global in 1997 and then sold to Maytag in 2001. It became part of the Whirlpool Corporation when it purchased Maytag in 2006.
The development of microwave technology during World War 2, such as the klystron and magnetron tubes and parabolic antennas made radiative (far-field) methods practical for the first time, and the first long-distance wireless power transmission was achieved in the 1960s by William C. Brown. In 1964 Brown invented the rectenna which could efficiently convert microwaves to DC power, and in 1964 demonstrated it with the first wireless-powered aircraft, a model helicopter powered by microwaves beamed from the ground. A major motivation for microwave research in the 1970s and 80s was to develop a solar power satellite. Conceived in 1968 by Peter Glaser, this would harvest energy from sunlight using solar cells and beam it down to Earth as microwaves to huge rectennas, which would convert it to electrical energy on the electric power grid. In landmark 1975 experiments as technical director of a JPL/Raytheon program, Brown demonstrated long-range transmission by beaming 475 W of microwave power to a rectenna a mile away, with a microwave to DC conversion efficiency of 54%. At NASA's Jet Propulsion Laboratory he and Robert Dickinson transmitted 30 kW DC output power across 1.5 km with 2.38 GHz microwaves from a 26 m dish to a 7.3 x 3.5 m rectenna array. The incident-RF to DC conversion efficiency of the rectenna was 80%. In 1983 Japan launched MINIX (Microwave Ionosphere Nonlinear Interaction Experiment), a rocket experiment to test transmission of high power microwaves through the ionosphere.
Porcelain was used in the first ceramic capacitors. In the early years of Marconi's wireless transmitting apparatus porcelain capacitors were used for high voltage and high frequency application in the transmitters. On the receiver side smaller mica capacitors were used for resonant circuits. Mica dielectric capacitors were invented in 1909 by William Dubilier. Prior to World War II, mica was the most common dielectric for capacitors in the United States.
The Microwave Research Institute (MRI) was founded in 1945 by Ernst Weber at the Polytechnic Institute of Brooklyn (which later became the Polytechnic Institute of New York University). Research conducted at the institute included work in the areas of "electromagnetic theory, antennas and radiation, network theory and microwave networks, microwave components and devices." MRI was internationally regarded as one of the foremost centers of research on microwave field theory in the world. In 1985 it was renamed the Weber Research Institute in honor of its founder.Among its most prominent members were Nathan Marcuvitz, Leo B. Felsen, Dante C. Youla and Arthur A. Oliner, all fellows of IEEE and members of the National Academy of Engineering. The institute has attracted researchers from all over the world, including Alexander Graham Bell Medal winner Tsuneo Nakahara, who in 1961 was a visiting research associate of the institute, and who went on to be vice chairman of the Sumitomo Electric Company, and Dr. Oguchi, who became chief engineer of Nippon Telegraph and Telephone. Another faculty member closely associated with MRI was KunMo Chung, Director of the Plasma Physics Laboratory from 1967 to 1975, who served as Minister of Science and Technology of South Korea two times and who was associated with numerous international science and technology agencies.
The first microphone that enabled proper voice telephony was the (loose-contact) carbon microphone (then called transmitter). This was independently developed around 1878 by David Edward Hughes in England and Emile Berliner and Thomas Edison in the US. Although Edison was awarded the first patent in mid-1877, Hughes had demonstrated his working device in front of many witnesses some years earlier, and most historians credit him with its invention.
German inventor Johann Philipp Reis designed an early sound transmitter that used a metallic strip attached to a vibrating membrane that would produce intermittent current. Better results were achieved with the "liquid transmitter" design in Scottish-American Alexander Graham Bell's telephone of 1876 – the diaphragm was attached to a conductive rod in an acid solution. These systems, however, gave a very poor sound quality.
The first microphone that enabled proper voice telephony was the (loose-contact) carbon microphone. This was independently developed by David Edward Hughes in England and Emile Berliner and Thomas Edison in the US. Although Edison was awarded the first patent (after a long legal dispute) in mid-1877, Hughes had demonstrated his working device in front of many witnesses some years earlier, and most historians credit him with its invention. The carbon microphone is the direct prototype of today's microphones and was critical in the development of telephony, broadcasting and the recording industries. Thomas Edison refined the carbon microphone into his carbon-button transmitter of 1886. This microphone was employed at the first ever radio broadcast, a performance at the New York Metropolitan Opera House in 1910.
In 1916, E.C. Wente of Western Electric developed the next breakthrough with the first condenser microphone. In 1923, the first practical moving coil microphone was built. The Marconi-Sykes magnetophone, developed by Captain H. J. Round, became the standard for BBC studios in London. This was improved in 1930 by Alan Blumlein and Herbert Holman who released the HB1A and was the best standard of the day.
Litke's wireless microphone was first tested at the Olympic trials held at Stanford University in 1959. Next, the American Broadcasting Company (ABC television) tested the microphone at the Democratic and Republican Conventions in 1960. Candidates John F. Kennedy and Richard Nixon were among the first celebrities to use the Vega-Mike. TV anchor John Daly praised Litke's invention on the ABC television news broadcast in July 1960. Daly introduced it to Americans with the words: "This is a Vega-Mike" and went on to explain it "is a wireless microphone, six inches long... without any wires of any kind..." Daly pointed out it could be used to broadcast "within the (convention) hall or outside... without the inconvenience of interconnecting microphone cables..." Even the Federal Communication Commission was impressed with it. The FCC gave him 12 frequencies instead of the one he was seeking.
Although he was the man responsible for its technology, Farnsworth appeared only once on a television program. On July 3, 1957, he was a mystery guest ("Doctor X") on the CBS quiz show "I've Got A Secret". He fielded questions from the panel as they unsuccessfully tried to guess his secret ("I invented electronic television."). For stumping the panel, he received $80 and a carton of Winston cigarettes. Host Garry Moore then spent a few minutes discussing with Farnsworth his research on such projects as high-definition television, flat-screen receivers, and fusion power. Farnsworth said, "There had been attempts to devise a television system using mechanical disks and rotating mirrors and vibrating mirrors—all mechanical. My contribution was to take out the moving parts and make the thing entirely electronic, and that was the concept that I had when I was just a freshman in high school in the Spring of 1921 at age 14." When Moore asked about others' contributions, Farnsworth agreed, "There are literally thousands of inventions important to television. I hold something in excess of 165 American patents." The host then asked about his current research, and the inventor replied, "In television, we're attempting first to make better utilization of the bandwidth, because we think we can eventually get in excess of 2,000 lines instead of 525 ... and do it on an even narrower channel ... which will make for a much sharper picture. We believe in the picture-frame type of a picture, where the visual display will be just a screen. And we hope for a memory, so that the picture will be just as though it's pasted on there."
The conventional telephone was invented independently by Alexander Bell and Elisha Gray in 1876. Antonio Meucci invented the first device that allowed the electrical transmission of voice over a line in 1849. However Meucci's device was of little practical value because it relied upon the electrophonic effect and thus required users to place the receiver in their mouth to "hear" what was being said. The first commercial telephone services were set-up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London.
The world’s first transistor computer was built at the University of Manchester in November 1953. The computer was built by Richard Grimsdale, then a research student in the Department of Electrical Engineering and later a Professor of Electronic Engineering at Sussex University. The machine used point-contact transistors, made in small quantities by STC and Mullard. These consisted of a single crystal of germanium with two fine wires, resembling the crystal and cat’s whisker of the 1920s. These transistors had the useful property that a single transistor could possess two stable states. ... The development of the machine was severely hampered by the unreliability of the transistors, which consumed 150 watts.
Warren S. Johnson (1847–1911) of Wisconsin patented a bi-metal room thermostat in 1883, and two years later filed a patent for the first multi-zone thermostatic control system.
Albert Butz (1849–1905) invented the electric thermostat and patented it in 1886.
The first widely used solid-state negative resistance device was the tunnel diode, invented in 1957 by Japanese physicist Leo Esaki. Because they have lower parasitic capacitance than vacuum tubes due to their small junction size, diodes can function at higher frequencies, and tunnel diode oscillators proved able to produce power at microwave frequencies, above the range of ordinary vacuum tube oscillators. Its invention set off a search for other negative resistance semiconductor devices for use as microwave oscillators, resulting in the discovery of the IMPATT diode, Gunn diode, TRAPATT diode, and others. In 1969 Kurokawa derived conditions for stability in negative resistance circuits. Currently negative differential resistance diode oscillators are the most widely used sources of microwave energy, and many new negative resistance devices have been discovered in recent decades.
Using the narrow definition of "operated by one person", the first personal computer was the ENIAC which became operational in 1946. It did not meet further definitions of affordable or easy to use. The Bendix G15 of 1956 was intended for use without an operating staff, and several hundred were made; it was too costly to be personally owned, however.
The development of transistors in 1948 by Bell Laboratories led to major improvements to the hearing aid. The transistor was invented by John Bardeen, Walter Brattain, and William Shockley. Transistors were created to replace vacuum tubes; they were small, required less battery power and had less distortion and heat than their predecessor. These vacuum tubes were typically hot and fragile, so the transistor was the ideal replacement.The 1952 Sonotone 1010 used a transistor stage along with vacuum tubes, to extend battery life. The size of these transistors led to developments in miniature, carbon microphones. These microphones could be mounted on various items, even eyeglasses. In 1951, Raytheon manufactured the transistor and was one of the first companies to mass-produce transistors to throughout America. Raytheon realized that their hearing aid only lasted short-term and began to sell the vacuum-tube hearing aids again along with transistor hearing aids.
Electric sound recording and reproduction are electrical or mechanical techniques and devices for the inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. Acoustic analog recording is achieved by a small microphone diaphragm that can record sound waves on a phonograph (in which a stylus senses grooves on a record) or magnetic tape. The first practical sound recording and reproduction device was the mechanical phonograph cylinder, invented by Thomas Edison in 1877 and patented in 1878. 
The next major technical development was the invention of the gramophone disc in 1889. For much of the 20th century, records were the most common way of selling sound recordings. The widespread availability of records and the development of radio broadcasting enabled a much larger proportion of people to listen to songs and pieces performed by the top artists, enabling the development of national and even international musical stars. In the 1970s, the compact cassette became a major consumer audio format. Advances in electronic and mechanical miniaturization led to the development of the Sony Walkman, a pocket-sized cassette player introduced in 1979, which allowed consumers to listen to their favourite albums outside of their home.
Microstrip, a type of transmission line usable at microwave frequencies, was invented with printed circuits in the 1950s. The ability to cheaply fabricate a wide range of shapes on printed circuit boards allowed microstrip versions of capacitors, inductors, resonant stubs, splitters, directional couplers, diplexers, filters and antennas to be made, thus allowing compact microwave circuits to be constructed. 
Transistors that operated at microwave frequencies were developed in the 1970s. The semiconductor gallium arsenide (GaAs) has a much higher electron mobility than silicon, so devices fabricated with this material can operate at 4 times the frequency of similar devices of silicon. Beginning in the 1970s GaAs was used to make the first microwave transistors, and it has dominated microwave semiconductors ever since. MESFETs (metal-semiconductor field-effect transistors), fast GaAs field effect transistors using Schottky junctions for the gate, were developed starting in 1968 and have reached cutoff frequencies of 100 GHz, and are now the most widely used active microwave devices. Another family of transistors with a higher frequency limit is the HEMT (high electron mobility transistor), a field effect transistor made with two different semiconductors, AlGaAs and GaAs, using heterojunction technology, and the similar HBT (heterojunction bipolar transistor).
The Cooke and Wheatstone telegraph was an early electrical telegraph system dating from the 1830s invented by English inventor William Fothergill Cooke and English scientist Charles Wheatstone. It was the first telegraph system to be put into commercial service. The receiver consisted of a number of needles which could be moved by electromagnetic coils to point to letters on a board. This feature was liked by early users who were unwilling to learn codes, and employers who did not want to invest in staff training.
In 1874, German scientist Karl Ferdinand Braun discovered the "unilateral conduction" across a contact between a metal and a mineral. Indian scientist Jagadish Chandra Bose was the first to use a crystal for detecting radio waves in 1894. The crystal detector was developed into a practical device for wireless telegraphy by Greenleaf Whittier Pickard, who invented a silicon crystal detector in 1903 and received a patent for it on November 20, 1906. Other experimenters tried a variety of other minerals as detectors. Semiconductor principles were unknown to the developers of these early rectifiers. During the 1930s understanding of physics advanced and in the mid 1930s researchers at Bell Telephone Laboratories recognized the potential of the crystal detector for application in microwave technology. Researchers at Bell Labs, Western Electric, MIT, Purdue and in the UK intensively developed point-contact diodes ("crystal rectifiers" or "crystal diodes") during World War II for application in radar. After World War II, AT&T used these in their microwave towers that criss-crossed the United States, and many radar sets use them even in the 21st century. In 1946, Sylvania began offering the 1N34 crystal diode. During the early 1950s, junction diodes were developed.
Once in the U.S., Zworykin found work at the Westinghouse laboratories in Pittsburgh, where he eventually had an opportunity to engage in television experiments. He came up with the main invention of the 20th century – electronic television. He applied for a television patent in the US in 1923. He summarized the resulting invention in two patent applications. The first, entitled "Television Systems", was filed on December 29, 1923, and was followed by a second application in 1925 of essentially the same content, but with minor changes and the addition of a Paget-type screen for color transmission and reception. He was awarded a patent for the 1925 application in 1928, and two patents for the 1923 application that was divided in 1931, although the equipment described was never successfully demonstrated.
The development of the cavity magnetron in the UK made possible the production of electromagnetic waves of a small enough wavelength (microwaves). American engineer Percy Spencer is generally credited with inventing the modern microwave oven after World War II from radar technology developed during the war. Named the "Radarange", it was first sold in 1946. Raytheon later licensed its patents for a home-use microwave oven that was first introduced by Tappan in 1955, but these units were still too large and expensive for general home use. Sharp Corporation introduced the first microwave oven with a turntable between 1964 and 1966. The countertop microwave oven was first introduced in 1967 by the Amana Corporation. After Sharp introduced low-cost microwave ovens affordable for residential use in the late 1970s, their use spread into commercial and residential kitchens around the world. In addition to their use in cooking food, types of microwave ovens are used for heating in many industrial processes.
An example of investment-specific technological progress is the microwave oven. The idea of the microwave came to be by accident: in 1946 an engineer noticed that a candy bar in his pocket had melted while working on something completely unrelated to cooking (Gallawa 2005). The development of this good, from melting the candy bar to the home appliance we know today, took time and the investment of resources to make a microwave small and cheap. The first microwave oven cost between 2000 and 3000 dollars and was housed in refrigerator-sized cabinets (Gallawa 2005)! Today, almost any college student can enjoy a 3-minute microwaveable meal in the smallest dorm room. But a microwave's uses do not stop at the dorm room. Many industries have found microwave heating advantageous: it has been used to dry cork, ceramics, paper, leather, and so on (Gallawa 2005). However, for either college students or firms to reap the benefits of quick warming, they must first "invest" in a microwave oven (that "embodies" the technological advance). To realize the benefits of investment-specific technological progress you must first invest in a technology that embodies it.
In the 1960s, Litton bought Studebaker's Franklin Manufacturing assets, which had been manufacturing magnetrons and building and selling microwave ovens similar to the Radarange. Litton then developed a new configuration of the microwave: the short, wide shape that is now common. The magnetron feed was also unique. This resulted in an oven that could survive a no-load condition: an empty microwave oven where there is nothing to absorb the microwaves. The new oven was shown at a trade show in Chicago, and helped begin a rapid growth of the market for home microwave ovens. Sales volume of 40,000 units for the U.S. industry in 1970 grew to one million by 1975. Market penetration was faster in Japan, due to a re-engineered magnetron allowing for less expensive units.
Several other companies joined in the market, and for a time most systems were built by defense contractors, who were most familiar with the magnetron. Litton was particularly well known in the restaurant business.
Formerly found only in large industrial applications, microwave ovens increasingly became a standard fixture of residential kitchens in developed countries. By 1986, roughly 25% of households in the U.S. owned a microwave oven, up from only about 1% in 1971; the U.S. Bureau of Labor Statistics reported that over 90% of American households owned a microwave oven in 1997. In Australia, a 2008 market research study found that 95% of kitchens contained a microwave oven and that 83% of them were used daily. In Canada, fewer than 5% of households had a microwave oven in 1979, but more than 88% of households owned one by 1998. In France, 40% of households owned a microwave oven in 1994, but that number had increased to 65% by 2004.