Lexikon's History of Computing

"Big Iron"
100 Giant Computers Before 1956

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Digital Computer Survey

The following is a listing of 100 early computers in use or under development from 1944 to 1955. This information is derived mainly from a 1953 survey of automatic digital computers conducted by the United States Office of Naval Research in Washington, D.C.

Some dates are approximate. Machines are not listed in exact chronological order of appearance. Where the dates 1954 and 1955 appear, these were estimates at the time as to when the computer would come on line. Previously available only in U.S. Government microfilm archives, it is provided here solely for educational and historical purposes. Any errors in dates or other information are just as they appeared in the original government document. Some of the machines listed never made it into full-scale use and production. Others, such as the UNIVAC, were the forerunners of many modern computers in use today.

For those machines with over 1,000 vacuum tubes, number of tubes is listed in red.

See also: Subject Index to Photos

Large Computers by Square Footage

Computer Name

Year

Components and General Size

ABC - Automatic Binary Computer

1953

1,200 tubes, 500 crystals, 50 relays. 250 square feet.

Harvard Mark I - Automatic Sequence Controlled Calculator (IBM "ASCC")

1944

The IBM Automatic Sequence Controlled Calculator (ASCC) was presented to Harvard University on August 7, 1944. The ASCC was over 51 feet long and 8 feet high. It contained 3,300 relay components, 2,200 counter wheels and weighed over 5 tons. It had no tubes, no crystals, many relays. 72 storage counters. Uses punched cards and punched tape.

The Harvard Mark 1 occupied 240 square feet. The Harvard Mark I was the first large scale, automatic, electromechanical digital computer. The Mark I basic concept was the developed by Howard Aiken. Aiken took the idea to Thomas Watson of IBM in 1937, who supported the project. The machine was designed with the help of IBM engineers Claire D. Lake, Benjamin M. Durfee, and Francis E. Hamilton. It was designed at the IBM Research Laboratory at Endicott New York. Power consumption, 25 kilowatts. The Mark I was used to compute solutions to various defense problems, including firing tables, logistics and a mathematical simulation project for the first atomic bomb. When the machine was put into operation at Harvard in 1944, it was used round the clock to support the U.S. Navy's Bureau of Ships. The Mark I was finally shut down and dismantled in 1959.

Components of the Mark I are now in the Smithsonian Institution in Washington, D.C., IBM headquarters in New York and at Harvard University.

Mark 22 Computer (Bell Computer, Model IV)

1945

2 square feet. No tubes, no crystals, 1,200 relays. Teletype relay. Cannot alter its instructions. Logical checks are incorporated into all circuits. Machine operates attended for 50 yours and unattended for 118 hours each week. Used to solve ordnance problems.

ENIAC - Electronic Numerical Integrator and Automatic Computer

1946

1,000 square feet. 200 Kilowatt power consumption. 18,000 tubes, 20 electronic registers. Weight: 30 tons. The ENIAC was the first electronic automatic computer. It was developed at the Moore School of Engineering by John Mauchly, J. Presper Eckert and others. Used for ballistic calculations, computing firing tables, computation problems relating to atomic energy research and general purpose applications. The ENIAC was operated at the Moore School until 1946 at which time it was transferred to the Aberdeen Proving Ground in Maryland. The ENIAC became operational again in 1947 and remained functional until October 2, 1955. Some components of the ENIAC are now in the Smithsonian Institution in Washington, D.C. Other ENIAC materials are located at the Historical Services Division of the Department of the Army in Washington.

Bell Computer, Model V

1947

1150 to 1600 square feet. 5,000 relays. General purpose,

Harvard Mark II - Aiken Relay Calculator

1948

50 feet by 60 feet. 2.5 kilowatt power consumption. 13,000 relays. Uses paper tape. Performs ballistic trajectory calculations.

IBM 604 Electronic Calculating Punch

1948

53" by 33". Utilized 1,100 vacuum tubes and 125 relays. Power consumption 6.9 kva. Used for repetitive calculations, each of which is a short sequence with very limited change in that sequence.

IBM 607A Calculating Punch

1948

5 cubic feet. 1.2 Kilowatt power consumption. 350 tubes, 2,500 crystal rectifiers. Used for calculation of real-time control problems.

Bell Computer, Model VI

1949

4,300 relays. 86 cold-cathode tubes. General purpose

BINAC - Binary Automatic Computer

1949

20 square feet. 700 tubes. Mercury delay lines. General purpose computer.

EDSAC I - Electronic Delay Storage Automatic Computer

1949

12 feet by 12 feet. 4,500 tubes. General purpose computer. 500 Kc clock frequency.

IBM CPC - Card Programmed Calculator

1949

53" by 33" for calculator itself, peripheral equipment took additional space, 1,238 vacuum tubes, 10 crystal rectifiers, and 1,229 relays. Power consumption 10.2 kvs. Used for lengthy sequential operations.

ERA 1101 - Engineering Research Associates

1950

110 sq. ft. 2,695 tubes, 2,385 crystal rectifiers, 135 relays. Magnetic drum technology. 400 Kc clock frequency. Used for general large-scale computations.

JAINCOMP-A

1950

1.2 square feet. 103 vacuum tubes, 350 crystal rectifiers. Punched card input. Used to test the feasibility of a compact, real-time computer operating in the parallel mode. Several programs were built in. Power consumption 450 watts.

SEAC

1950

150 sq. ft., 1,300 tubes, 15,800 crystal diodes, 10 relays. General computation services and engineering development

SWAC

1950

75 square feet, 2,300 tubes, 3,000 crystals, magnetic drum, electrostatic storage. Power consumption 30 kw. General purpose computer for problems with small input and output. The SWAC was a parallel computer utilizing Williams' tube memory. Development of the SWAC was begun in January 1949. It was dedicated in August 1950 and, at that time, was the fastest computer in existence. The SWAC was originally named the ZEPHER but was later renamed the SWAC. By 1953, the SWAC was producing approximately 53 hours per week of useful programming. The SWAC was eventually moved from the National Bureau of Standards to the Engineering Building at UCLA. It remained in operation until December 1967. Components of the SWAC are now with the Museum of Science and Industry in Los Angeles.

USAF Fairchild Computer

1950

600 sq. ft., 2,200 tubes, 20 crystals, 50 relays, magnetic tape. Used for inversion of matrices, solution of simultaneous linear equations.

Whirlwind I

1950

The Whirlwind took up 3,300 square feet within in a two-story building. The drum storage system and data communications interface was located on the ground floor. The CPU, control console and CRT displays were located on the second floor. Power supplies were located in the building's basement and the roof was covered with air conditioning equipment to cool down the system. Power generation was approximately 150 KW. The Whirlwind contained 12,500 tubes, 23,803 crystal rectifiers, 1,800 relays, magnetic drum, magnetic tape. Used for real-time control problems, also general purpose calculations. The computer was a 16-bit parallel, single-address, binary computer. Instructions and data occupied 16 bit words in memory. The Whirlwind utilized magnetic tape and magnetic drum for auxiliary storage. Forester used iron core memory for main computer memory storage. The Whirlwind was in operation until 1959.

Z4

1950

160 square feet, 2,200 relays, mechanical storage, paper tape. Used to solve differential equations.

Burroughs Laboratory Computer

1951

20 square feet. 700 tubes. Mercury delay lines. General purpose computer.

CSIRO Mark I (Australia)

1951

400 square feet. 1,800 tubes, 1,500 crystal rectifiers, 30 relays. Used for matrix operations, differential equations, function tables and data analysis. 333 Kc clock frequency.

Elecom 200 - Electronic Computer

1951

85 sq. ft. 500 tubes, 4,500 crystal rectifiers, 120 relays. Magnetic drum. General numerical computation; ordinance supply control studies.

Harvard Mark III

1951

40 feet by 40 feet. 40 kilowatt power consumption. 5,000 tubes, 1,300 crystal diodes, 1,500 relays. Uses magnetic drum and magnetic tape. Best suited for problems requiring large internal storage.

JAINCOMP-B

1951

4.75 sq. ft. 409 vacuum tubes, 4,032 crystal rectifiers. Used real-time computation with fixed programs and little input. Power consumption 2.75 Kva.

LEO I

1951

800 sq. ft. 6,000 tubes, 1,500 crystal rectifiers, 120 relays. The LEO is patterned after the EDSAC I. Used for General purpose, routine commercial clerical work.

MADDIDA

1951

10 square feet. 150 tubes, 1,200 crystals. Used to determine solutions of differential equations.

Manchester Electronic Computer

1951

2 bays, 16 feet by 18 feet. 1,800 pentodes, 2,000 vacuum diodes. Used as general purpose computer.

ONR Relay Computer

1951

40 sq. ft., 655 tubes, 332 crystals, 734 relays, magnetic drum. General purpose, small input/output.

Remington-Rand 409-2 and 409-2R

1951

43.6 sq. ft., 1,500 tubes, 200 relays, used for punch-card accounting and scientific computing.

UNIVAC I

1951 

25 feet by 50 feet, 5,600 tubes, 18,000 crystal diodes, 300 relays. Serial circuitry, 2.25 MHz bit rate, internal storage capacity 1,000 words or 12,000 characters. Mercury delay line, magnetic tapes, typewriter output. Used for general purpose computing with large amounts of input and output. Power consumption 120 kva. Processing speed: arithmetic functions, 0.525 ms; multiplication, 2.150 ms; division, 3,890 ms, comparison, 0.365 ms. A total of 46 UNIVAC I models were made.

CADAC - Cambridge Digital Automatic Computer

1952

General purpose computation, not requiring large storage. 3.5 feet by 2.5 feet. Magnetic Drum technology. 100 Kc clock rate. 195 tubes, 2,500 crystal rectifiers, 10 relays.

EDVAC - Electronic Discrete Variable Automatic Computer

1952

1,200 square feet, 3,600 tubes, 10,000 crystals. 996.75 Kc clock frequency. Mercury delay line; input and output were handled through punched paper tape and IBM cards. 50 Kilowatt power consumption. The conceptual design for the EDVAC was completed in 1946 and the system was delivered to the Ballistic Research Laboratories at Aberdeen, Maryland in 1949. The EDVAC was considered fully operational by 1951. It was in used until December of 1962.

ELECOM 100 - Electronic Computer

1952

25 square feet. 240 tubes, 2,000 crystal diodes, 12 relays. General purpose numerical computation.

Elecom 120 - Electronic Computer

1952

13 sq. ft. 350 tubes, 4,000 crystal rectifiers, 35 relays. 105 Kc clock frequency. General purpose applications.  

Gi - Gottingen

1952

125 square feet. 476 tubes, 101 relays, 7.2 Kc clock frequency. Performs numerical integration and other repetitive calculations.

Harvard Mark IV - Harvard Magnetic Drum Calculator

1952

30 feet by 10 feet. 25 kilowatt power consumption. 4,000 tubes, many crystal rectifiers. Uses magnetic drum. General purpose computer.

Harwell Computer

1952

Utilizes relays, double-length dekatron accumulator

Hughes Airborne Control Computer

1952

5 cubic feet. 1.2 Kilowatt power consumption. 350 tubes, 2,500 crystal rectifiers. Used for calculation of real-time control problems.

IASC - Institute for Advanced Study Computer

1952

100 square feet. Used electrostatic technology (Williams tube), magnetic drum, 2,300 tubes, no crystals, no relays. Power 15 kw. General purpose computer.

ILLIAC - Illinois Automatic Computer

1952

25 square feet. 2,774 tubes, no crystals, one relay. Utilized electrostatic technology (Williams tube). Used for computations not involving large input or output.

MANIAC

1952

20 sq. ft. 2,500 tubes, 800 crystals, no relays. Logical design is modeled on IAS computer. Used for general purpose computing.

MOSAIC

1952

Floor area 24 feet by 18 feet. Used about 6,000 tubes; about 2,000 crystals. Mercury delay line, punched cards, paper tape, typewriter print out. Best suited for trial analysis, addition, subtraction, multiplication, logical operations. Power consumption 30 kw.

ORDVAC

1952

800 sq. ft., 2,700 tubes. Electrostatic (Williams tube), used for scientific computation.

UTEC

1952

375 sq. ft., 400 tubes, 200 crystals, 25 relays. Used for mathematical problems, limited storage, input and output.

ACE Pilot Model - Automatic Computing Engine

1953

152 square feet floor space. Approximately 800 tubes.

ALWAC - Axel Wernner-Gren Automatic Computer

1953

28 feet by 116 feet. 67 Kc clock rate. Magnetic Drum, punch paper tape

APE (R) C - All-Purpose Electronic (Rayon) Computer

1953

General purpose statistical computer. 20 square foot. 420 tubes, 30 relays. 30 Kc clock. Magnetic Drum.

APE (X) C - All-Purpose Electronic (X-ray) Computer

1953

20 square foot. 310 tubes, 3 relays. 60 Kc clock. Magnetic Drum.

AVIDAC - Argonne's Version of IAS Digital Automatic Computer

1953

3,500 cubic feet. Williams tubes, Magnetic Tape. 2.800 tubes, no relays. Problem solving computer

CA/DIC - California Digital Computer

1953

General purpose, large memory, small output, moderate speed. 100 square feet. 1,100 tubes, 1,300 crystal diodes, 12 relays. Magnetic Drum.

CADAC 107A - Cambridge Digital Automatic Computer

1953

8 square feet. Magnetic Drum. 300 tubes, 4,000 crystal rectifiers. General purpose computer

Circle Computer (Hogan Labs, Westinghouse, Army)

1953

15 square feet. 700 tubes. General purpose, scientific computer. 80 Kc clock frequency.

Consolidated Engineering Corp. Model 36-101 Computer System

1953

150 square feet. 1,200 tubes. 3,000 crystal rectifiers. Magnetic Drum technology. 140 Kc clock frequency. General purpose, mathematical and scientific computation.

CRC 105 Decimal Digital Differential Analyzer

1953

8 square feet. 200 tubes, 3,000 crystal diodes. Used for solutions to ordinance and some partial differential equations.

CRC 107 - General Purpose Computer

1953

500 sq. ft. 850 tubes, 8,000 crystal rectifiers, 50 relays. Used for general purpose problems requiring large storage. 100 Kc clock frequency. Waste-water cooled. Magnetic Drum and magnetic tape storage.

DYSEAC

1953

General purpose simulation, some classes of real-time. 500 tubes plus 350 in each memory cabinet. 20,500 crystal rectifiers. Germanium diode switches, tube amplifiers and delay lines. Magnetic drum and tape.

EDPM Type 701 - Electronic Data Processing Machine

1953

1200 square feet. 4,000 tubes, 13,000 crystal rectifiers. General purpose computer. Magnetic drum and tape. 1 Mc clock frequency.

Elliot HRDC Computer 401 Mark I

1953

13 ft by 2 ft. 500 tubes, 2,500 crystals. Magnetic drum. General purpose computer. 333 Kc clock frequency.

ERA 1102 - Engineering Research Associates

1953

110 sq. ft. 2,200 tubes, 3,000 crystal rectifiers, 90 relays. Magnetic drum technology. 500 Kc clock frequency. Used for general purpose computation, on-line data reduction.

ERA 1103 - Engineering Research Associates

1953

300 sq. f. 4,500 tubes, 6,000 crystal rectifiers, 150 relays. Magnetic drum technology. 500 Kc clock frequency. Used for general large scale computation, real-time control and emulation.

FLAC - Florida Automatic Computer

1953

400 square feet. 800 tubes. 15,000 crystals, 30 relays. General purpose scientific computations. 1 Mc clock frequency. Magnetic tape, mercury delay line.

GAMMA 3

1953

2 feet by 4.5 feet. 400 tubes, 7,000 crystal rectifiers, 200 relays. Accounting and math problems requiring limited fast storage capacity.

IBM 607 Electronic Calculating Punch

1953

58" by 33". Utilized 1,300 to 2,400 vacuum tubes, 150 relays. Power consumption 9.11 kva. Used for problems requiring moderate storage and computation.

JAINCOMP-C

1953

4.2 square feet. 801 vacuum tubes, large number of crystal rectifiers. Used for real-time computation or general purpose computing.

MIDAC

1953

845 sq. ft. 1,100 tubes, 20,000 crystals, 120 relays. Used as general purpose computer.

MINAC

1953

1 sq. ft. floor area. 90 tubes, 900 crystal rectifiers. General purpose scientific and engineering computation.

MINIAC

1953

16 square foot. Magnetic drum, tape reader, tape punch, typewriter. General purpose computer.

MONROBOT

1953

16 sq. ft. 650 tubes, 200 crystals, 15 relays. General purpose computing, some antenna design, some mapping.

NICHOLAS

1953

Punched paper tape. General purpose computer.

NORC

1953

The NORC utilized a microsecond delay unit, diode switching and a 3,600 word cathode ray tube storage unit. One of its functions included calculating Pi to 3,000 places as well as calculating the exact positions of the earth, moon and other planets in space up to the year 2,000. In the summer of 1955, the NORC was installed at the Naval Proving Grounds at Dahlgren, Virginia. It remained there until it was replaced by the IBM Stretch computer (IBM 7030) in 1958.

Norwegian Computer

1953

2 meters by 3 meters. About 450 tubes, 200 crystal rectifiers, 10 relays. Magnetic drum, General purpose computer.

OARAC

1953 

Area requirements 80 sq. ft. About 1,400 tubes, 7,000 crystals, 240 relays. Magnetic drum, magnetic tape. General purpose computer. Power consumption, 25 kw.

ORACLE

1953

1,500 sq. ft., 3,500 tubes, modeled after the IAS computer. General purpose computer, magnetic tape, 30 kw power consumption.

PTERA

1953

Six feet by 12 feet, 650 tubes, 20 crystals, 120 relays, magnetic drum. General purpose computer.

RAYDAC

1953 

200 sq. ft., 5,200 tubes, 17,300-crystal rectifiers, 630 relays, used for data reduction, large-scale computation. Power 28 kw.

Rechenautomat IPM

1953

300 tubes, 1,000 crystal rectifiers, 100 relays, magnetic drum. General purpose computer.

SITDDA

1953

300 square feet, 450 tubes, 3,000 crystal rectifiers, 25 relays, used for hydrodynamic research.

T.R.E. Computer

1953

14 feet by 6 feet, 2,000 tubes, 1,000 crystals, 25 relays. Electrostatic storage, magnetic drum. General purpose computer. Power consumption 10 kw.

The Logistics Computer

1953

190 square feet. 3,500 tubes, 2,000 crystals, 200 relays. Used for data handling, short simple routines repeated many times. Magnetic drum technology.

Tokyo Mark I

1953

80 square feet, 1,500 relays. Constructed primarily as a pilot model.

Z5

1953

2,500 relays. General purpose optical computations.

ABRK - Binary Automatisk Rela-Kalkylator

1953c

710 square feet. 7,500 relays. General purpose machine.

ARRA - Automatishe Relais Rekenmachine Amsterdam

1954

80 by 16 feet, plus desk. Magnetic Drum, paper tape. 500 tubes, 20000 selenium rectifiers, 15 relays. General purpose computer.

BDDDA - Bendix Decimal Digital Differential Analyzer

1954

Tubes (number unknown), 2,400 crystals. Magnetic Drum technology.

CUBA - Calculator Universal Binaire de l'Armement

1954

1,000 square feet. Germanium diodes, 100 Kc clock frequency. Used for multiplication. Magnetic Drum technology.

G2 - Gottingen

1954

200 square feet. 1,100 tubes, 92 Kc clock frequency. Performs general purpose numerical analysis and algebra.

IBM Type 650 Magnetic-Drum Data Processing Machine

1954

2,218 tubes, 3,960 diodes, 600 relays, power consumption 16.8 kva. Used for scientific, commercial computing, utility, billing, and general purpose.

IRSIA-FHRS Computer

1954

25 feet by 25 feet. 2,000 tubes, 1,000 selenium rectifiers, and 1,500 germanium diodes. 4.5 kw power. General purpose computer.

JOHNNIAC

1954

600 sq. ft. Used about 3,000 tubes, no crystals, about 200 relays. Machine was used for scientific calculations for general research. Machine was a modified IAS type computer with selectron and magnetic-drum memory.

MSAC

1954

1,400 sq. ft., 3,000 tubes, 20,000 crystals, 200 relays. Mercury delay lines, teletype tape, General purpose, small, input-output problems.

NAREC

1954

Floor area requirements 100 square feet. 2,000 tubes, 20,000 crystals, no relays. Magnetic drum, magnetic tape, paper tape punch, flexowriter. General purpose computer. Power consumption 40 kw.

OMIBAC

1954

Used 3,300 tubes, magnetic drum, general purpose computer, primary use ballistic and flight-path studies. Power consumption 12 kw. 

PXRM

1954

800 square feet, 1,700 tubes, 2,000 crystal rectifiers, general purpose computer.

TAC - Tokyo Automatic Computer

1954

2,300 square feet, 1,200 tubes, 2,400 crystal rectifiers. General purpose computer. Power consumption 7.5 kw.

Tokyo Mark II (Large Scale Automatic Relay Computer)

1954

50 square feet, 50,000 relays, general purpose computer.

WISC

1954

12 square feet, 700 tubes, 60 crystal rectifiers, magnetic drum. Used as general purpose computer, small input- output problems.

BKSK - Binar Klektronisk Sekvens-Kalkylator

1954c

General purpose, government, scientific and industrial computing. 70 square feet. Magnetic Drum technology. 160 kc clock rate. 2,250 tubes, 200 crystal rectifiers.

EDPM Type 704 - Electronic Data Processing Machine

1955

1,200 square feet. 4,000 tubes, 13,000 crystal rectifiers. General purpose computer.

R 4 S

1955

1,200 tubes, 500 crystals, 200 relays, used for partial differential equations.

TC-1 - Telemeter Computer Model 1

1955

30 square feet, 3,500 tubes, no crystals, no relays. Used for general scientific computation.

Largest Computer

The SAGE Computer System, begun in the 1950's and made operational by the early 1960's was the largest computer system ever built.

250 tons, 60,000 vacuum tubes, 20,000 square feet

 

 

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