The RCA BIZMAC was a
vacuum tube
A vacuum tube, electron tube, thermionic 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. It ...
computer
A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic set ...
manufactured by
RCA
RCA Corporation was a major American electronics company, which was founded in 1919 as the Radio Corporation of America. It was initially a patent pool, patent trust owned by General Electric (GE), Westinghouse Electric Corporation, Westinghou ...
from 1956 to 1962. Although RCA was noted for their pioneering work in
transistor
A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch electrical signals and electric power, power. It is one of the basic building blocks of modern electronics. It is composed of semicondu ...
s, 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 of floor space with up to 30,000 tubes, 70,000
diode
A diode is a two-Terminal (electronics), terminal electronic component that conducts electric current primarily in One-way traffic, one direction (asymmetric electrical conductance, conductance). It has low (ideally zero) Electrical resistance ...
s, and 35,000
magnetic core
A magnetic core is a piece of magnetism, magnetic material with a high magnetic permeability used to confine and guide magnetic fields in electrical, electromechanical and magnetic devices such as electromagnets, transformers, electric motors, ele ...
s.
It weighed about .
History
In 1949, the Mutual Assistance Program (MAP)—later known as the Military Assistance Program—was started by the United States to provide military assistance and supplies to foreign countries needing to rebuild their military defenses after
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
.
In 1951, RCA was awarded a $4.5 million military contract to build a data processing machine to support the logistics necessary for the MAP. The result was the BIZMAC computer system.
The first BIZMAC machine was installed at the Ordnance Tank-Automotive Command (OTAC) in
Detroit, Michigan
Detroit ( , ) is the List of municipalities in Michigan, most populous city in the U.S. state of Michigan. It is situated on the bank of the Detroit River across from Windsor, Ontario. It had a population of 639,111 at the 2020 United State ...
in 1956. Eventually, BIZMAC computer systems were also installed at
Higbee Department Stores,
Travelers Insurance Company
The Travelers Companies, Inc., commonly known as Travelers, is an American multinational insurance company. It is the second-largest writer of U.S. commercial property casualty insurance, and the sixth-largest writer of U.S. personal insurance t ...
, and
New York Life Insurance Company
New York Life Insurance Company (NYLIC) is the third-largest life insurance company and the largest mutual insurance, mutual life insurance company in the United States, and is ranked #69 on the 2025 Fortune 500 list of the largest U.S. corporat ...
.
The huge BIZMAC system was very quickly made obsolete by faster and more reliable computer systems, including
IBM
International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...
's
705
__NOTOC__
Year 705 ( DCCV) was a common year starting on Thursday of the Julian calendar, the 705th year of the Common Era (CE) and Anno Domini (AD) designations, the 705th year of the 1st millennium, the 5th year of the 8th century, and the 6t ...
computer as well as RCA's own transistorized
501
__NOTOC__
Year 501 ( DI) was a common year starting on Monday of the Julian calendar. At the time, it was known as the Year of the Consulship of Avienus and Pompeius (or, less frequently, year 1254 ''Ab urbe condita''). The denomination 501 fo ...
computer. The BIZMAC was taken offline from the OTAC in 1962.
Only about six BIZMAC computers were actually made.
Features
A unique feature of the BIZMAC was the use of hundreds of permanently mounted
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 long archival stability.
...
s. This meant that tape data could be accessed immediately without constant mounting and dismounting individual tapes.
Engineers
One of the original engineers of the BIZMAC was
Arnold Spielberg
Arnold Meyer Spielberg (February 6, 1917 – August 25, 2020) was an American electrical engineer who was instrumental in contributions to "real-time data acquisition and recording that significantly contributed to the definition of modern f ...
, the father of film director and producer
Steven Spielberg
Steven Allan Spielberg ( ; born December 18, 1946) is an American filmmaker. A major figure of the New Hollywood era and pioneer of the modern blockbuster, Spielberg is widely regarded as one of the greatest film directors of all time and is ...
. Spielberg designed and patented an electronic library system used for searching data stored on magnetic tapes.
[https://www.computer.org/web/awards/pioneer-arnold-spielberg Arnold M. Spielberg: 2006 Computer Pioneer Award Recipient]
See also
*
List of vacuum-tube computers
Vacuum-tube computers, now called first-generation computers, are programmable digital computers using vacuum-tube logic circuitry. They were preceded by systems using electromechanical relays and followed by systems built from discrete transi ...
*
History of computing hardware
The history of computing hardware spans the developments from early devices used for simple calculations to today's complex computers, encompassing advancements in both analog and digital technology.
The first aids to computation were purely mec ...
References
{{Reflist
External links
BIZMAC Computer History Archives Project - Cold War Military TechnologyVintage RCA Computers - A Brief Look at the RCA 501 - History ArchivesCharacteristics of the' RCA BIZMAC Computer
1950s computers
Early computers