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Eimac
Eimac is a trade mark of Eimac Products, part of the Microwave Power Products Division of Communications & Power Industries. It produces power vacuum tubes for radio frequency applications such as broadcast and radar transmitters. The company name is an initialism from the names of the founders, William Eitel and Jack McCullough. History The San Francisco Bay area was one of the early centers of amateur radio activity and experimentation, containing about 10% of the total operators in the US. Amateur radio enthusiasts sought vacuum tubes that would perform at higher power and on higher frequencies than those then available from RCA, Western Electric, General Electric, and Westinghouse. Additionally, they required tubes that would operate with the limited voltages available from typical amateur power supplies. While employed by the small San Francisco, California manufacturing firm of Heintz & Kaufman which manufactured custom radio equipment, Bill Eitel (amateur radio call sign W6U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eimac Tube
Eimac is a trade mark of Eimac Products, part of the Microwave Power Products Division of Communications & Power Industries. It produces power vacuum tubes for radio frequency applications such as broadcast and radar transmitters. The company name is an initialism from the names of the founders, William Eitel and Jack McCullough. History The San Francisco Bay area was one of the early centers of amateur radio activity and experimentation, containing about 10% of the total operators in the US. Amateur radio enthusiasts sought vacuum tubes that would perform at higher power and on higher frequencies than those then available from RCA, Western Electric, General Electric, and Westinghouse. Additionally, they required tubes that would operate with the limited voltages available from typical amateur power supplies. While employed by the small San Francisco, California manufacturing firm of Heintz & Kaufman which manufactured custom radio equipment, Bill Eitel (amateur radio call ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Bruno
San Bruno (Spanish for " St. Bruno") is a city in San Mateo County, California, United States, incorporated in 1914. The population was 43,908 at the 2020 United States Census. The city is between South San Francisco and Millbrae, adjacent to San Francisco International Airport and Golden Gate National Cemetery; it is approximately south of Downtown San Francisco. Geography The city is located between South San Francisco and Millbrae, adjacent to San Francisco International Airport to the east and Golden Gate National Cemetery to the northwest. It is approximately south of Downtown San Francisco. According to the United States Census Bureau, the city has a total area of , all of it land. The city spreads from the mostly flat lowlands near San Francisco Bay into the foothills of the Santa Cruz Mountains, which rise to more than above sea level in Crestmoor and more than above sea level in Portola Highlands. San Bruno City Hall sits at an official elevation of 41 feet (1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental electronic functions such as signal amplifier, amplification and current rectifier, rectification. Non-thermionic types such as a vacuum phototube, however, achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light intensities. In both types, the electrons are accelerated from the cathode to the anode by the electric field in the tube. The simplest vacuum tube, the diode (i.e. Fleming valve), invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Electrons can only flow in one direction through the device—fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications & Power Industries
CPI International, Inc. is the holding company for Communications & Power Industries, the largest manufacturer and rebuilder of electron devices (primarily vacuum tubes) in the United States. CPI was founded in 1995 when Varian Associates sold its electron-device business (the original business of its founders) to concentrate on medical systems. Its major subsidiaries include Eimac (which manufactures new vacuum tubes for the broadcasting, radar, medical systems, and other applications), Econco (a vacuum-tube rebuilder), Beverly Microwave Systems, and Radant Technologies. CPI International made its initial public offering An initial public offering (IPO) or stock launch is a public offering in which shares of a company are sold to institutional investors and usually also to retail (individual) investors. An IPO is typically underwritten by one or more investme ... in April, 2006. CPI's Econco division remanufactures Eimac and Machlett power tubes. In February 2011, an af ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KSBR
KSBR (88.5 FM, "The SoCal Sound") is a non-commercial educational radio station licensed to Mission Viejo, California and broadcasting to the Orange County area. The station is owned by Saddleback College and airs adult album alternative (AAA) and Americana music with a mix of legends, new music, and local music with some specialty programming on weekends. KSBR is simulcast with KCSN in Northridge, California. History KSBR signed on in 1975 as a Class D, 10-watt student-run station and a limited coverage area of only a few miles from the campus of Saddleback Community College. In 1979, with grants from CPB and NTIA, the signal was upgraded to a Class A, covering most of Orange County and the station signed on as Orange County's first National Public Radio affiliate with a staff of professional and student broadcasters. The program schedule at first employed an eclectic, free-form mix of rock music, drama and locally produced talk shows but, with a growing news and public af ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrode
A tetrode is a vacuum tube (called ''valve'' in British English) having four active electrodes. The four electrodes in order from the centre are: a thermionic cathode, first and second grids and a plate (called ''anode'' in British English). There are several varieties of tetrodes, the most common being the screen-grid tube and the beam tetrode. In screen-grid tubes and beam tetrodes, the first grid is the control grid and the second grid is the screen grid. In other tetrodes one of the grids is a control grid, while the other may have a variety of functions. The tetrode was developed in the 1920s by adding an additional grid to the first amplifying vacuum tube, the triode, to correct limitations of the triode. During the period 1913 to 1927, three distinct types of tetrode valves appeared. All had a normal control grid whose function was to act as a primary control for current passing through the tube, but they differed according to the intended function of the other gri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadcasting
Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a one-to-many model. Broadcasting began with AM radio, which came into popular use around 1920 with the spread of vacuum tube radio transmitters and receivers. Before this, all forms of electronic communication (early radio, telephone, and telegraph) were one-to-one, with the message intended for a single recipient. The term ''broadcasting'' evolved from its use as the agricultural method of sowing seeds in a field by casting them broadly about. It was later adopted for describing the widespread distribution of information by printed materials or by telegraph. Examples applying it to "one-to-many" radio transmissions of an individual station to multiple listeners appeared as early as 1898. Over the air broadcasting is usually associated with radio and television, thou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navigation Radar
Radar navigation is the utilization of marine and aviation radar systems for vessel and aircraft navigation. When a craft is within radar range of land or special radar aids to navigation, the navigator can take distances and angular bearings to charted objects and use these to establish arcs of position and lines of position on a chart.Maloney, 2003:744. A fix consisting of only radar information is called a ''radar fix''.Bowditch, 2002:816. Some types of radar fixes include the relatively self-explanatory methods of "range and bearing to a single object,"National Imagery and Mapping Agency, 2001:163. "two or more bearings," "tangent bearings," and "two or more ranges." Parallel indexing is a technique defined by William Burger in the 1957 book ''The Radar Observer's Handbook''.National Imagery and Mapping Agency, 2001:169. This technique involves creating a line on the screen that is parallel to the ship's course, but offset to the left or right by some distance. This pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Frequency
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies; these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. Different sources specify different upper and lower bounds for the frequency range. Electric current Electric currents that oscillate at radio frequencies (RF currents) have special properties not shared by direct current or lower audio frequency alternating current, such as the 50 or 60 Hz current used in electrical power distribution. * Energy from RF currents in conductors can radiate into space as electromagnetic waves ( radio waves). This is the basis of radio technology. * RF current does not penetrate deeply into electrica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klystron Tube
A klystron is a specialized linear-beam vacuum tube, invented in 1937 by American electrical engineers Russell and Sigurd Varian,Pond, Norman H. "The Tube Guys". Russ Cochran, 2008 p.31-40 which is used as an amplifier for high radio frequencies, from UHF up into the microwave range. Low-power klystrons are used as oscillators in terrestrial microwave relay communications links, while high-power klystrons are used as output tubes in UHF television transmitters, satellite communication, radar transmitters, and to generate the drive power for modern particle accelerators. In a klystron, an electron beam interacts with radio waves as it passes through resonant cavities, metal boxes along the length of a tube. The electron beam first passes through a cavity to which the input signal is applied. The energy of the electron beam amplifies the signal, and the amplified signal is taken from a cavity at the other end of the tube. The output signal can be coupled back into the input cavi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
