The UNIVAC 1105 was a follow-on computer to the

UNIVAC 1103A The UNIVAC 1103 or ERA 1103, a successor to the UNIVAC 1101, was a computer system designed by Engineering Research Associates and built by the Remington Rand corporation in October 1953. It was the first computer for which Seymour Cray was cred ...

introduced by

Sperry Rand Sperry Corporation was a major American equipment and electronics company whose existence spanned more than seven decades of the 20th century. Sperry ceased to exist in 1986 following a prolonged hostile takeover bid engineered by Burroughs ...

in September 1958. The UNIVAC 1105 used 21 types of

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 kn ...

s, 11 types of

diode A diode is a two-terminal electronic component that conducts current primarily in one direction (asymmetric conductance); it has low (ideally zero) resistance in one direction, and high (ideally infinite) resistance in the other. A diode ...

s, 10 types of

transistor upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch e ...

s, and three core types. The UNIVAC 1105 had either 8,192 or 12,288 words of 36-bit magnetic

core memory Core or cores may refer to: Science and technology * Core (anatomy), everything except the appendages * Core (manufacturing), used in casting and molding * Core (optical fiber), the signal-carrying portion of an optical fiber * Core, the centra ...

, in two or three banks of 4,096 words each. Magnetic

drum memory Drum memory was a magnetic data storage device invented by Gustav Tauschek in 1932 in Austria. Drums were widely used in the 1950s and into the 1960s as computer memory. For many early computers, drum memory formed the main working memory ...

provided either 16,384 or 32,768 words, in one or two drums with 16,384 words each. Sixteen to twenty-four

UNISERVO II The UNISERVO tape drive was the primary I/O device on the UNIVAC I computer. It was the first tape drive for a commercially sold computer. The UNISERVO used metal tape: a thin strip of nickel-plated phosphor bronze (called Vicalloy) 1200 feet lon ...

tape drive A tape drive is a data storage device that reads and writes data on a magnetic tape. Magnetic tape data storage is typically used for offline, archival data storage. Tape media generally has a favorable unit cost and a long archival stability. ...

s were connected, with a maximum capacity (not counting block overhead) of 1,200,000 words per tape. Fixed-point numbers had a one-bit sign and a 35-bit value, with negative values represented in

ones' complement The ones' complement of a binary number is the value obtained by inverting all the bits in the binary representation of the number (swapping 0s and 1s). The name "ones' complement" (''note this is possessive of the plural "ones", not of a sing ...

format.

Floating-point In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can b ...

numbers had a one-bit sign, an eight-bit characteristic, and a 27-bit mantissa.

Instructions Instruction or instructions may refer to: Computing * Instruction, one operation of a processor within a computer architecture instruction set * Computer program, a collection of instructions Music * Instruction (band), a 2002 rock band from Ne ...

had a six-bit operation code and two 15-bit operand addresses. A complete UNIVAC 1105 computer system required 160 kW of power (175 KVA, 0.9 power factor) and an

air conditioning Air conditioning, often abbreviated as A/C or AC, is the process of removing heat from an enclosed space to achieve a more comfortable interior environment (sometimes referred to as 'comfort cooling') and in some cases also strictly controlling ...

unit with a power of at least 35 tons (123 kW) for cooling input water. The computer system weighed about with a floor loading of 47 lb/ft² (230 kg/m²) and required a room 49 x 64 x 10 ft (15 x 20 x 3 m). The floor space for the computer was approximately 3,752 ft² (350 m²). The power, refrigeration and equipment room was approximately 2,450 ft² (230 m²).

Cost, price and rental rates

Chapel Hill

In 1959, a Univac 1105 located in the basement of Phillips Hall of The

University of North Carolina at Chapel Hill A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States ...

was one of three computers of its type. It was intended primarily for the

United States Census Bureau The United States Census Bureau (USCB), officially the Bureau of the Census, is a principal agency of the U.S. Federal Statistical System, responsible for producing data about the American people and economy. The Census Bureau is part of the ...

, which had one of its own;

Armour Institute of Technology Illinois Institute of Technology (IIT) is a private research university in Chicago, Illinois. Tracing its history to 1890, the present name was adopted upon the merger of the Armour Institute and Lewis Institute in 1940. The university has prog ...

had the other. The Chapel Hill unit cost $2.4 million, with the improvements to the basement, including 16-inch concrete walls to protect it from nuclear attack, added $1.2 million. Its memory was less than 50 kilobytes, or one 8 1/2 x 11 document, with the capability of adding 30,000 numbers per second. The Univac was 60 feet long, weighed 19 tons, and used 7200 vacuum tubes. Its printer had a speed of 600 lines per minute.

References

External links

{{commons category
BRL REPORT NO. 1115 March 1961: UNIVAC 1105
by Martin H. Weik 1105 Vacuum tube computers Computer-related introductions in 1958

Cost, price and rental rates

Chapel Hill

See also

References

External links