A transistor computer, now often called a second-generation computer, [1] is a computer which uses discrete transistors instead of vacuum tubes. The first generation of electronic computers used vacuum tubes, which generated large amounts of heat, were bulky and unreliable. A second-generation computer, through the late 1950s and 1960s featured circuit boards filled with individual transistors and magnetic-core memory. These machines remained the mainstream design into the late 1960s, when integrated circuits started appearing and led to the third-generation computer.
The University of Manchester's experimental Transistor Computer was first operational in November 1953 and it is widely believed to be the first transistor computer to come into operation anywhere in the world. There were two versions of the Transistor Computer, the prototype, operational in 1953, and the full-size version, commissioned in April 1955. [2] The 1953 machine had 92 point-contact transistors and 550 diodes, manufactured by STC. It had a 48-bit machine word. The 1955 machine had a total of 200 point-contact transistors and 1,300 point diodes, [3] which resulted in a power consumption of 150 watts. There were considerable reliability problems with the early batches of transistors and the average error-free run in 1955 was only 1.5 hours. The Transistor Computer also used a small number of tubes in its clock generator, so it was not the first fully transistorized machine. [4]
The design of a full-size Transistor Computer was subsequently adopted by the Manchester firm of Metropolitan-Vickers, who changed all the circuits to use more reliable junction transistors. The production version was known as the Metrovick 950 and was built from 1956 to the extent of six [3] or seven machines, which were "used commercially within the company" [5] or "mainly for internal use". [3]
During the mid-1950s a series of similar machines appeared. These included the Bell Laboratories TRADIC, completed in January 1954, which used a single high-power output vacuum-tube amplifier to supply its 1-MHz clock power. [6]
The first fully transistorized computer was either the Harwell CADET, which first operated in February 1955, although the price paid for this was that it operated only at the slow speed of 58 kHz,[ citation needed ] or the prototype IBM 604 transistor calculator. The Burroughs Corporation claimed the SM-65 Atlas ICBM / THOR ABLE guidance computer (MOD 1) that it delivered to the US Air Force at the Cape Canaveral missile range in June 1957 was "the world's first operational transistorized computer".[ citation needed ] MIT's Lincoln Laboratory started developing a transistorized computer the TX-0 in 1956.
Further transistorized computers became operational in Japan (ETL Mark III, July 1956), in Canada (DRTE Computer, 1957), and in Austria, (Mailüfterl, May 1958), [7] these being the first transistorized computers in Asia, Canada and mainland Europe respectively.
In April 1955, [8] IBM announced the IBM 608 transistor calculator, which was first shipped in December 1957. [9] IBM and several historians thus consider the IBM 608 the first all solid-state computing machine commercially marketed. [8] [10] [11] [12] The development of the 608 was preceded by the prototyping of an experimental all-transistor version of the 604. This was built and demonstrated in October 1954, but was not commercialized. [9] [11] [13]
The Philco Transac models S-1000 scientific computer and S-2000 electronic data processing computer were early commercially produced large-scale all-transistor computers; they were announced in 1957 but did not ship until sometime after the fall of 1958. The Philco computer name "Transac" stands for Transistor-Automatic-Computer. Both of these Philco computer models used the surface-barrier transistor in their circuitry designs, the world's first high-frequency transistor suitable for high-speed computers. [14] [15] [16] The surface-barrier transistor was developed by Philco in 1953. [17]
RCA shipped the RCA 501 its first all-transistor computer in 1958. [18]
In Italy, Olivetti's first commercial fully transistorized computer was the Olivetti Elea 9003, sold from 1959. [19]
IBM, which dominated the data processing industry through most of the 20th century, introduced its first commercial transistorized computers beginning in 1958, with the IBM 7070, a ten-digit-word decimal machine. [20] It was followed in 1959 by the IBM 7090, a 36-bit scientific machine, the highly popular IBM 1401 designed to replace punched card tabulating machines, and the desk-sized 1620, a variable length decimal machine. IBM's 7000 and 1400 series included many variants on these designs, with different data formats, instruction sets and even different character encodings, but all were built using the same series of electronics modules, the IBM Standard Modular System (SMS). [21]
Developers of the TX-0 left to form the Digital Equipment Corporation in 1957. Transistorized from the beginning, early DEC products included the PDP-1, PDP-6, PDP-7 and early PDP-8s, the last starting the minicomputer revolution. Later models of the PDP-8 beginning with PDP-8I [22] in 1968 used integrated circuits making them third generation computers
In 1964, IBM announced its System/360, a collection of computers covering a wide range of capabilities and prices with a unified architecture, to replace its earlier computers. Unwilling to bet the company on the immature monolithic IC technology of the early 1960s, IBM built the S/360 series using IBM's Solid Logic Technology (SLT) modules. SLT could package several individual transistors and individual diodes with deposited resistors and interconnections in a module one-half inch square, roughly the equivalent logic of the earlier IBM Standard Modular System card, but unlike monolithic IC manufacturing, the diodes and transistors in an SLT module were individually placed and connected at the end of each module's assembly. [21]
First generation computers were largely out of reach of schools and hobbyists who wished to build their own, largely because of the cost of the large number of vacuum tubes required (though relay-based computer projects were undertaken [23] ). The fourth generation (VLSI) was also largely out of reach, too, due to most of the design work being inside the integrated circuit package (though this barrier, too, was later removed [24] ). So, second and third generation computer design (transistors and LSI) were perhaps the best suited to being undertaken by schools and hobbyists. [25]
The history of computing hardware covers the developments from early simple devices to aid calculation to modern day computers.
The TX-0, for Transistorized Experimental computer zero, but affectionately referred to as tixo, was an early fully transistorized computer and contained a then-huge 64K of 18-bit words of magnetic-core memory. Construction of the TX-0 began in 1955 and ended in 1956. It was used continually through the 1960s at MIT. The TX-0 incorporated around 3,600 Philco high-frequency surface-barrier transistors, the first transistor suitable for high-speed computers. The TX-0 and its direct descendant, the original PDP-1, were platforms for pioneering computer research and the development of what would later be called computer "hacker" culture. For MIT, this was the first computer to provide a system console which allowed for direct interaction, as opposed to previous computers, which required the use of punched card as a primary interface for programmers debugging their programs. Members of MIT's Tech Model Railroad Club, "the very first hackers at MIT", reveled in the interactivity afforded by the console, and were recruited by Marvin Minsky to work on this and other systems used by Minsky's AI group.
The IBM 604 Electronic Calculating Punch was the world's first mass-produced electronic calculator along with its predecessor the IBM 603. It was an electronic unit record machine that could perform multiple calculations, including division. It was invented and developed by Ralph Palmer, Jerrier Haddad and Byron Phelps. It was introduced by IBM in 1948.
The history of computing hardware starting at 1960 is marked by the conversion from vacuum tube to solid-state devices such as transistors and then integrated circuit (IC) chips. Around 1953 to 1959, discrete transistors started being considered sufficiently reliable and economical that they made further vacuum tube computers uncompetitive. Metal–oxide–semiconductor (MOS) large-scale integration (LSI) technology subsequently led to the development of semiconductor memory in the mid-to-late 1960s and then the microprocessor in the early 1970s. This led to primary computer memory moving away from magnetic-core memory devices to solid-state static and dynamic semiconductor memory, which greatly reduced the cost, size, and power consumption of computers. These advances led to the miniaturized personal computer (PC) in the 1970s, starting with home computers and desktop computers, followed by laptops and then mobile computers over the next several decades.
The Fifth Generation Computer Systems was a 10-year initiative begun in 1982 by Japan's Ministry of International Trade and Industry (MITI) to create computers using massively parallel computing and logic programming. It aimed to create an "epoch-making computer" with supercomputer-like performance and to provide a platform for future developments in artificial intelligence. FGCS was ahead of its time, and its excessive ambitions led to commercial failure. However, on a theoretical level, the project spurred the development of concurrent logic programming.
Resistor–transistor logic (RTL), sometimes also known as transistor–resistor logic (TRL), is a class of digital circuits built using resistors as the input network and bipolar junction transistors (BJTs) as switching devices. RTL is the earliest class of transistorized digital logic circuit; it was succeeded by diode–transistor logic (DTL) and transistor–transistor logic (TTL).
In computer engineering, a logic family is one of two related concepts:
Solid Logic Technology (SLT) was IBM's method for hybrid packaging of electronic circuitry introduced in 1964 with the IBM System/360 series of computers. It was also used in the 1130, announced in 1965. IBM chose to design custom hybrid circuits using discrete, flip chip-mounted, glass-encapsulated transistors and diodes, with silk-screened resistors on a ceramic substrate, forming an SLT module. The circuits were either encapsulated in plastic or covered with a metal lid. Several of these SLT modules were then mounted on a small multi-layer printed circuit board to make an SLT card. Each SLT card had a socket on one edge that plugged into pins on the computer's backplane.
The TRADIC was the first transistorized computer in the USA, completed in 1954.
Philco is an American electronics manufacturer headquartered in Philadelphia. Philco was a pioneer in battery, radio, and television production. In 1961, the company was purchased by Ford and, from 1966, renamed "Philco-Ford". Ford sold the company to GTE in 1974, and it was purchased by Philips in 1981. In North America, the Philco brand is owned by Philips. In other markets, the Philco International brand is owned by Electrolux.
A hybrid integrated circuit (HIC), hybrid microcircuit, hybrid circuit or simply hybrid is a miniaturized electronic circuit constructed of individual devices, such as semiconductor devices and passive components, bonded to a substrate or printed circuit board (PCB). A PCB having components on a Printed Wiring Board (PWB) is not considered a true hybrid circuit according to the definition of MIL-PRF-38534.
A direct-coupled amplifier or DC amplifier is a type of amplifier in which the output of one stage of the amplifier is coupled to the input of the next stage in such a way as to permit signals with zero frequency, also referred to as direct current, to pass from input to output. This is an application of the more general direct coupling. It was invented by Harold J Paz and Francis P. Keiper Jr. in 1955. It displaced the triode vacuum tube amplifier designed by Lee de Forest. Almost all vacuum tube circuit designs are now replaced with direct coupled transistor circuit design. It is the first transistor amplifier design that did not include coupling capacitors. The direct-coupled amplifier allowed analog circuits to be built smaller with the elimination of coupling capacitors and removed the lower frequency limitation that is dependent on capacitors.
The surface-barrier transistor is a type of transistor developed by Philco in 1953 as an improvement to the alloy-junction transistor and the earlier point-contact transistor. Like the modern Schottky transistor, it offered much higher speed than earlier transistors and used metal–semiconductor junctions, but unlike the schottky transistor, both junctions were metal–semiconductor junctions.
The Harwell CADET was the first fully transistorised computer in Europe, and may have been the first fully transistorised computer in the world.
This list compares various amounts of computing power in instructions per second organized by order of magnitude in FLOPS.
The IBM 608 Transistor Calculator, a plugboard-programmable unit, was the first IBM product to use transistor circuits without any vacuum tubes and is believed to be the world's first all-transistorized calculator to be manufactured for the commercial market. Announced in April 1955, it was released in December 1957. The 608 was withdrawn from marketing in April 1959.
The Elea was a series of mainframe computers Olivetti developed starting in the late 1950s. The system, made entirely with transistors for high performance, was conceived, designed and developed by a small group of researchers led by Mario Tchou (1924–1961), with industrial design by Ettore Sottsass. The ELEA 9001 was the first solid-state computer designed and manufactured in Italy. The acronym ELEA stood for Elaboratore Elettronico Aritmetico and was chosen with reference to the ancient Greek colony of Elea, home of the Eleatic school of philosophy. About forty units were placed with customers. In August 1964, only a few years after releasing the 9003, Olivetti's mainframe business was sold to GE.
The RCA BIZMAC was a vacuum tube computer manufactured by RCA from 1956 to 1962. Although RCA was noted for their pioneering work in transistors, RCA decided to build a vacuum tube computer instead of a transistorized computer. It was the largest vacuum tube computer of its time in 1956, occupying 20,000 sq ft (1,900 m2) of floor space with up to 30,000 tubes, 70,000 diodes, and 35,000 magnetic cores. It weighed about 26,500 lb (12,000 kg).
Philco was one of the pioneers of transistorized computers, also known as second generation computers. After the company developed the surface barrier transistor, which was much faster than previous point-contact types, it was awarded contracts for military and government computers. Commercialized derivatives of some of these designs became successful business and scientific computers. The TRANSAC Model S-1000 was released as a scientific computer. The TRANSAC S-2000 mainframe computer system was first produced in 1958, and a family of compatible machines, with increasing performance, was released over the next several years.