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IBM 421
The IBM 421 accounting machine saw use in the 1960s. The largely-mechanical IBM 421 read 80-column punch cards and could print upper-case letters of the alphabet, the decimal digits 0 to 9, a period (.), and plus and minus signs. The operation of the 421 was directed by the use of a removable control panel and a carriage tape. By means of the control panel, any column of the card could be wired to any print column, by means of a wire link (the end terminals of which were manually inserted into slots in the control panel). After manual wiring, the control panel was inserted in the side of the machine, and a hand-operated lever moved the control panel so that the wire links made contact with corresponding terminals in the machine. The 421 had 64 positions of memory, typically used to store data from a leading punch card. There were also three external program switches (Minor, Major and Super Major) that were used to alter the function of the plug board Program Selectors. IBM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MNACTEC Keyboards (30316694693)
The National Museum of Science and Industry of Catalonia ( ca, Museu Nacional de la Ciència i de la Tècnica de Catalunya) known by its acronym (mNACTEC) is one of the three national museums of Catalonia, located in Terrassa, near Barcelona. Its mission is to showcase and promote an understanding of scientific, technical and industrial culture, and furthermore to preserve, study and present the establishment and evolution of scientific and technical advances in Catalonia, their industrial application, and above all their social implications and impact. The museum is an Anchor point on the European Route of Industrial Heritage. Building The museum is housed in the iconic ''Vapor Aymerich, Amat i Jover'' in Terrassa near Barcelona. It was designed by the Catalan architect Lluís Muncunill for Messrs Aymerich, Amat i Jover in 1909. He solved the problem of roofing the immense weaving shed with row upon row of 161 shell-shaped half arches, each with gently curving windows: this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accounting Machine
An accounting machine, or bookkeeping machine or recording-adder, was generally a calculator and printer combination tailored for a specific commercial activity such as billing, payroll, or ledger. Accounting machines were widespread from the early 1900s to 1980s, but were rendered obsolete by the availability of low-cost computers such as the IBM PC. This type of machine is generally distinct from unit record equipment (some unit record machines were also called accounting machines). List of Vendors/Accounting Machines * Burroughs Sensimatic * Burroughs Sensitronic * Burroughs B80 * Burroughs E103 * Burroughs Computer F2000 * Burroughs L500 * Burroughs E1400 Electronic Computing/Accounting Machine with Magnetic Striped Ledger * Dalton Adding Machine Company * Electronics Corporation of America: Magnefile-B * Electronics Corporation of America: Magnefile-D * Elliott-Fisher * Federal Adding Machines * IBM 632 * IBM 858 Cardatype Accounting Machine * IBM 6400 Series * La ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punched Card
A punched card (also punch card or punched-card) is a piece of stiff paper that holds digital data represented by the presence or absence of holes in predefined positions. Punched cards were once common in data processing applications or to directly control automated machinery. Punched cards were widely used through much of the 20th century in the data processing industry, where specialized and increasingly complex unit record equipment, unit record machines, organized into semiautomatic data processing systems, used punched cards for data input, output, and storage. The IBM 12-row/80-column punched card format came to dominate the industry. Many early digital computers used punched cards as the primary medium for input of both computer programs and Data (computing), data. While punched cards are now obsolete as a storage medium, as of 2012, some voting machines still used punched cards to record votes. They also had a significant cultural impact. History The idea of contr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plugboard
A plugboard or control panel (the term used depends on the application area) is an array of jacks or sockets (often called hubs) into which patch cords can be inserted to complete an electrical circuit. Control panels are sometimes used to direct the operation of unit record equipment, cipher machines, and early computers. Unit record equipment Main article: Unit record equipment The earliest machines were hardwired for specific applications. Control panels were introduced in 1906 for the Hollerith Type 1 Tabulatorphoto of Type 3 with built-in control panel here. Removable control panels were introduced with the Hollerith ( IBM) type 3-S tabulator in the 1920s. Applications then could be wired on separate control panels, and inserted into tabulators as needed. Removable control panels came to be used in all unit record machines where the machines use for different applications required rewiring. IBM removable control panels ranged in size from 6 1/4" by 10 3/4" (for ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carriage Control Tape
A carriage control tape was a loop of punched tape that was used to synchronize rapid vertical page movement in most IBM and many other line printers from unit record days through the 1980's. The tape loop was as long as the length of a single page. A pin wheel moved the tape accurately using holes in the center of the tape. A hole punched in one of the other channels represented a particular position on the page. Channel one was typically used to indicate the top of the page and might be the only channel used. Another channel might indicate the summary line on an invoice, enabling rapid skipping to that line. IBM provides a special manual punch that allowed accurate placement of the channel punches. Skipping occurred under computer control, but a form feed switch on the printer control panel allowed a manual skip to the top of the page. The tapes could be easily changed when new, continuously fed forms were loaded into the printer. Forms control buffer Newer printers use a "form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Memory
In computing, memory is a device or system that is used to store information for immediate use in a computer or related computer hardware and digital electronic devices. The term ''memory'' is often synonymous with the term ''primary storage'' or '' main memory''. An archaic synonym for memory is store. Computer memory operates at a high speed compared to storage that is slower but less expensive and higher in capacity. Besides storing opened programs, computer memory serves as disk cache and write buffer to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as not needed by running software. If needed, contents of the computer memory can be transferred to storage; a common way of doing this is through a memory management technique called ''virtual memory''. Modern memory is implemented as semiconductor memory, where data is stored within memory cells built from MOS transistors and other components on an integrated c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Journal Of Statistics
Indian or Indians may refer to: Peoples South Asia * Indian people, people of Indian nationality, or people who have an Indian ancestor ** Non-resident Indian, a citizen of India who has temporarily emigrated to another country * South Asian ethnic groups, referring to people of the Indian subcontinent, as well as the greater South Asia region prior to the 1947 partition of India * Anglo-Indians, people with mixed Indian and British ancestry, or people of British descent born or living in the Indian subcontinent * East Indians, a Christian community in India Europe * British Indians, British people of Indian origin The Americas * Indo-Canadians, Canadian people of Indian origin * Indian Americans, American people of Indian origin * Indigenous peoples of the Americas, the pre-Columbian inhabitants of the Americas and their descendants ** Plains Indians, the common name for the Native Americans who lived on the Great Plains of North America ** Native Americans in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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