# Friden Calculator Repair Manual

History of computing hardware Wikipedia. Parts from four early computers, 1. From left to right ENIAC board, EDVAC board, ORDVAC board, and BRLESC I board, showing the trend toward miniaturization. The history of computing hardware covers the developments from early simple devices to aid calculation to modern day computers. Before the 2. 0th century, most calculations were done by humans. Early mechanical tools to help humans with digital calculations, such as the abacus, were called calculating machines, by proprietary names, or even as they are now, calculators. The machine operator was called the computer. The first aids to computation were purely mechanical devices which required the operator to set up the initial values of an elementary arithmetic operation, then manipulate the device to obtain the result. Later, computers represented numbers in a continuous form, for instance distance along a scale, rotation of a shaft, or a voltage. Numbers could also be represented in the form of digits, automatically manipulated by a mechanical mechanism. Although this approach generally required more complex mechanisms, it greatly increased the precision of results. A series of breakthroughs, such as miniaturized transistor computers, and the integrated circuit, caused digital computers to largely replace analog computers. The cost of computers gradually became so low that by the 1. Early deviceseditAncient eraeditSuanpan the number represented on this abacus is 6,3. Devices have been used to aid computation for thousands of years, mostly using one to one correspondence with fingers. Punched tape or perforated paper tape is a form of data storage, consisting of a long strip of paper in which holes are punched to store data. Now effectively. The earliest counting device was probably a form of tally stick. Later record keeping aids throughout the Fertile Crescent included calculi clay spheres, cones, etc. The use of counting rods is one example. The abacus was early used for arithmetic tasks. What we now call the Roman abacus was used in Babylonia as early as c. BC. Since then, many other forms of reckoning boards or tables have been invented. In a medieval European counting house, a checkered cloth would be placed on a table, and markers moved around on it according to certain rules, as an aid to calculating sums of money. Several analog computers were constructed in ancient and medieval times to perform astronomical calculations. These included the south pointing chariot c. BC from ancient China, and the astrolabe and Antikythera mechanism from the Hellenistic world c. JRWjc355vw/hqdefault.jpg' alt='Friden Calculator Repair Manual' title='Friden Calculator Repair Manual' />BC. In Roman Egypt, Hero of Alexandria c. AD made mechanical devices including automata and a programmable cart. Other early mechanical devices used to perform one or another type of calculations include the planisphere and other mechanical computing devices invented by Abu Rayhan al Biruni c. AD 1. 00. 0 the equatorium and universal latitude independent astrolabe by Ab Ishq Ibrhm al Zarql c. AD 1. 01. 5 the astronomical analog computers of other medieval Muslim astronomers and engineers and the astronomical clock tower of Su Song 1. Song dynasty. The castle clock, a hydropowered mechanical astronomical clock invented by Ismail al Jazari in 1. Ramon Llull invented the Lullian Circle a notional machine for calculating answers to philosophical questions in this case, to do with Christianity via logical combinatorics. Shop from the worlds largest selection and best deals for Vintage Electronics. Shop with confidence on eBay The history of computing hardware covers the developments from early simple devices to aid calculation to modern day computers. Before the 20th century, most. Friden Calculator Repair Manual' title='Friden Calculator Repair Manual' />This idea was taken up by Leibniz centuries later, and is thus one of the founding elements in computing and information science. Renaissance calculating toolsedit. A set of John Napiers calculating tables from around 1. Scottish mathematician and physicist John Napier discovered that the multiplication and division of numbers could be performed by the addition and subtraction, respectively, of the logarithms of those numbers. While producing the first logarithmic tables, Napier needed to perform many tedious multiplications. It was at this point that he designed his Napiers bones, an abacus like device that greatly simplified calculations that involved multiplication and division. Since real numbers can be represented as distances or intervals on a line, the slide rule was invented in the 1. Napiers work, to allow multiplication and division operations to be carried out significantly faster than was previously possible. Edmund Gunter built a calculating device with a single logarithmic scale at the University of Oxford. His device greatly simplified arithmetic calculations, including multiplication and division. William Oughtred greatly improved this in 1. He followed this up with the modern slide rule in 1. Gunter rules, held together with the hands. Slide rules were used by generations of engineers and other mathematically involved professional workers, until the invention of the pocket calculator. Mechanical calculatorseditWilhelm Schickard, a German polymath, designed a calculating machine in 1. Napiers rods with the worlds first mechanical adding machine built into the base. Because it made use of a single tooth gear there were circumstances in which its carry mechanism would jam. A fire destroyed at least one of the machines in 1. Schickard was too disheartened to build another. In 1. 64. 2, while still a teenager, Blaise Pascal started some pioneering work on calculating machines and after three years of effort and 5. He built twenty of these machines called Pascals calculator or Pascaline in the following ten years. Nine Pascalines have survived, most of which are on display in European museums. A continuing debate exists over whether Schickard or Pascal should be regarded as the inventor of the mechanical calculator and the range of issues to be considered is discussed elsewhere. Lenovo B560 Wifi Driver Windows 7 there. Gottfried Wilhelm von Leibniz invented the stepped reckoner and his famous stepped drum mechanism around 1. He attempted to create a machine that could be used not only for addition and subtraction but would utilise a moveable carriage to enable long multiplication and division. Leibniz once said It is unworthy of excellent men to lose hours like slaves in the labour of calculation which could safely be relegated to anyone else if machines were used. However, Leibniz did not incorporate a fully successful carry mechanism. Leibniz also described the binary numeral system,2. However, up to the 1. Charles Babbages machines of the 1. ENIAC of 1. 94. 5 were based on the decimal system. Around 1. 82. 0, Charles Xavier Thomas de Colmar created what would over the rest of the century become the first successful, mass produced mechanical calculator, the Thomas Arithmometer. It could be used to add and subtract, and with a moveable carriage the operator could also multiply, and divide by a process of long multiplication and long division. It utilised a stepped drum similar in conception to that invented by Leibniz. Mechanical calculators remained in use until the 1. Punched card data processingeditIn 1. Joseph Marie Jacquard developed a loom in which the pattern being woven was controlled by a paper tape constructed from punched cards. The paper tape could be changed without changing the mechanical design of the loom. This was a landmark achievement in programmability. His machine was an improvement over similar weaving looms. Punched cards were preceded by punch bands, as in the machine proposed by Basile Bouchon.