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Car Phone
A car phone is a mobile radio telephone specifically designed for and fitted into an automobile. This service originated with the Bell System and was first used in St. Louis, Missouri, on June 17, 1946. Overview United States The original equipment weighed , and there were initially only three channels for all the users in the metropolitan area (other sources claim six channels). On October 2, 1946, Motorola communications equipment carried the first calls on Illinois Bell Telephone Company's new car radiotelephone service in Chicago. Due to the small number of radio frequencies available, the service quickly reached capacity. In 1964 AT&T introduced the Improved Mobile Telephone Service (IMTS). More licenses were added, bringing the total to 32 channels across three bands (See IMTS frequencies). This service was used at least into the 1980s in large portions of North America. In 1968, almost 22 years after the initial network, the US government started to consider reservin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motorola Carphone Model TLD-1100, 1964, View 1 - National Electronics Museum - DSC00184
Motorola, Inc. () was an American Multinational corporation, multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul Galvin (businessman), Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been radio-related communication equipment such as two-way radios, consumer Walkie-talkie, walkie-talkies, Cellular network, cellular infrastructure, Cellular phones, mobile phones, satellite communicators, pagers, as well as cable modems and semiconductors. After having lost $4.3 billion from 2007 to 2009, Motorola was split into two independent public companies: Motorola Solutions (its legal successor) and Motorola Mobility (spun off), on January 4, 2011. Motorola designed and sold wireless network equipment such as Cellular network, cellular transmission base stations and signal amplifiers. Its business and government customers consisted mainly of wireless voice and broadband systems (used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
B-Netz
B-Netz was an analog, commercial mobile radio telephone network that was operated by the Deutsche Bundespost in Germany (at first only West Germany) from 1972 until 1994. The system was also implemented in neighboring countries Austria, The Netherlands and Luxembourg. The B refers to the fact that it was the country's second public mobile telephone network, following the A-Netz. As opposed to its predecessor, it featured direct-dialing (so that human operators were not required to connect calls). The frequency plan originally included only 38 channels (with one call possible per frequency channel), but it was upgraded to incorporate the A-Netz frequencies when that network was retired in 1980. The upgraded network had 78 channels and is sometimes referred to as the B2-Netz. A major limitation of system was that, in order to reach a subscriber, one had to know his location since the handset would assume the local area code of the base station serving it. Handoff was not pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Improved Mobile Telephone Service
The Improved Mobile Telephone Service (IMTS) was a pre- cellular VHF/ UHF radio system which linked to the public telephone network. IMTS was the radiotelephone equivalent of land dial phone service. Introduced in 1964, it replaced Mobile Telephone Service (MTS) and improved on most MTS systems by offering direct-dial rather than connections through a live operator, and full-duplex operation so both parties could talk at the same time. Technical Information The original Bell System US and Canadian mobile telephone system includes three frequency bands, VHF Low (35-44 MHz, 9 channels), VHF High (152-158 MHz, 11 channels in the U.S., 13 channels in Canada), and UHF (454-460 MHz, 12 channels). Alternative names were "Low Band", "High band" and "UHF". In addition to the Bell system ( wireline incumbent) channels, another 7 channels at VHF, and 12 channels at UHF were granted to non-wireline companies designated as "RCCs" (Radio Common Carriers). These RCC channe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile Telephone Service
The Mobile Telephone Service (MTS) was a pre- cellular VHF radio system that linked to the Public Switched Telephone Network (PSTN). MTS was the radiotelephone equivalent of land dial phone service. The Mobile Telephone Service was one of the earliest mobile telephone standards. It was operator assisted in both directions, meaning that if one were called from a land line the call would be routed to a mobile operator, who would route it to one's phone. Similarly, to make an outbound call one had to go through the mobile operator, who would ask for the mobile number and the number to be called, and would then place the call. This service originated with the Bell System, and was first used in St. Louis, Missouri, United States on June 17, 1946. The original equipment weighed , and there were initially only 3 channels for all the users in the metropolitan area, later more licenses were added bringing the total to 32 channels across 3 bands (see IMTS frequencies). This service was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Mobile Phone System
Advanced Mobile Phone System (AMPS) was an analog mobile phone system standard originally developed by Bell Labs and later modified in a cooperative effort between Bell Labs and Motorola. It was officially introduced in the Americas on October 13, 1983,Private Line and was deployed in many other countries too, including Israel in 1986, Australia in 1987, Singapore in 1988, and Pakistan in 1990. It was the primary analog mobile phone system in North America (and other locales) through the 1980s and into the 2000s. As of February 18, 2008, carriers in the United States were no longer required to support AMPS and companies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TACS
Total Access Communication System (TACS) and ETACS are variants of Advanced Mobile Phone System (AMPS) which were announced as the choice for the first two UK national cellular systems in February 1983, less than a year after the UK government announced the T&Cs for the two competing mobile phone networks in June 1982. This 1G technology is now obsolete. History Vodafone (known then as Racal-Vodafone) opted for a £30 million turnkey contract from Ericsson (ERA) to design, build and set up its initial network of 100 base station sites. Cellnet (then known Telecom Securicor Cellular Radio Ltd) used development labs in the facilities at General Electric (later made part of Motorola) based at Lynchburg, Virginia, United States. The reason Cellnet used the General Electric labs was because the AMPS system was already in development there, and the company had set up a production facility in readiness for AMPS production in 1985 which the Cellnet TACS was to share. In March 1984 de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alejandro Cervantes Delgado
Alejandro Cervantes Delgado (January 24, 1926 - September 17, 2000) was a Mexican economist and politician affiliated with the Institutional Revolutionary Party (PRI). Cervantes Delgado was elected to the Chamber of Deputies for the third district of Guerrero in the 1973 mid-term election. He later served as governor of Guerrero List of governors of Guerrero since it became a Federated state, state of Mexico in 1917. References See also * List of Mexican state governors {{DEFAULTSORT:Governor Of Guerrero Governors of Guerrero, * Lists of governors of State ... from 1981 to 1987, where he was notable for his efforts to reconcile groups with differing political opinions. References Governors of Guerrero Institutional Revolutionary Party politicians 1926 births 2000 deaths Politicians from Guerrero People from Chilpancingo 20th-century Mexican politicians Members of the Senate of the Republic (Mexico) Members of the Chamber of Deputies (Mexico) Nation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guerrero
Guerrero, officially the Free and Sovereign State of Guerrero, is one of the 32 states that compose the administrative divisions of Mexico, 32 Federal Entities of Mexico. It is divided into Municipalities of Guerrero, 85 municipalities. The state has a population of about 3.5 million people. It is located in southwest Mexico and is bordered by the states of Michoacán to the north and west, the State of Mexico and Morelos to the north, Puebla to the northeast and Oaxaca to the east. In addition to the capital city, Chilpancingo and the largest city Acapulco, other cities in Guerrero include Petatlán, Ciudad Altamirano, Guerrero, Ciudad Altamirano, Taxco, Iguala, Ixtapa, and Zihuatanejo. Today, it is home to a number of indigenous communities, including the Nahuas, Mixtecs, Tlapanec people, Tlapanecs, Amuzgos, and formerly Cuitlatec people, Cuitlatecs. It is also home to communities of Afro-Mexicans in the Costa Chica of Guerrero, Costa Chica region. The state was named after Vic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilogram
The kilogram (also spelled kilogramme) is the base unit of mass in the International System of Units (SI), equal to one thousand grams. It has the unit symbol kg. The word "kilogram" is formed from the combination of the metric prefix kilo- (meaning one thousand) and gram; it is colloquially shortened to "kilo" (plural "kilos"). The kilogram is an SI base unit, defined ultimately in terms of three defining constants of the SI, namely a specific transition frequency of the caesium-133 atom, the speed of light, and the Planck constant. A properly equipped metrology laboratory can calibrate a mass measurement instrument such as a Kibble balance as a primary standard for the kilogram mass. The kilogram was originally defined in 1795 during the French Revolution as the mass of one litre of water (originally at 0 °C, later changed to the temperature of its maximum density, approximately 4 °C). The current definition of a kilogram agrees with this original defini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Tit
The Eurasian blue tit (''Cyanistes caeruleus'') is a small passerine bird in the tit (bird), tit family, Paridae. It is easily recognizable by its blue and yellow plumage and small size. Eurasian blue tits, usually resident bird, resident and bird migration, non-migratory birds, are widespread and a common resident breeder throughout temperate and subarctic Europe and the western Palearctic in deciduous or mixed woodlands with a high proportion of oak. They usually nest in tree holes, although they easily adapt to nest boxes where necessary. Their main rival for nests and in the search for food is the larger and more common great tit (''Parus major''). The Eurasian blue tit prefers insects and spiders for its diet. Outside the breeding season, they also eat seeds and other vegetable-based foods. The birds are noted for their acrobatic skills, as they can hold on to the outermost branches of trees and shrubs and hang upside down when looking for food. Taxonomy The Eurasian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mexico
Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundary, maritime boundaries with the Pacific Ocean to the west, the Caribbean Sea to the southeast, and the Gulf of Mexico to the east. Mexico covers 1,972,550 km2 (761,610 sq mi), and is the List of countries by area, thirteenth-largest country in the world by land area. With a population exceeding 130 million, Mexico is the List of countries by population, tenth-most populous country in the world and is home to the Hispanophone#Countries, largest number of native Spanish speakers. Mexico City is the capital and List of cities in Mexico, largest city, which ranks among the List of cities by population, most populous metropolitan areas in the world. Human presence in Mexico dates back to at least 8,000 BC. Mesoamerica, considered a cradle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stasi
The Ministry for State Security (, ; abbreviated MfS), commonly known as the (, an abbreviation of ), was the Intelligence agency, state security service and secret police of East Germany from 1950 to 1990. It was one of the most repressive police organisations in the world, infiltrating almost every aspect of life in East Germany, using torture, intimidation and a vast network of informants to crush dissent. The function of the Stasi in East Germany (the GDR) resembled that of the KGB in the Soviet Union, in that it served to maintain state authority and the position of the ruling party, in this case the Socialist Unity Party of Germany (SED). This was accomplished primarily through the use of a network of civilian informants (called Unofficial collaborator, unofficial collaborators) who contributed to the arrest of approximately 250,000 people in East Germany. It also had a large elite paramilitary force, the Felix Dzerzhinsky Guards Regiment, that served as its armed wing. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
