TRADIC
Encyclopedia
The TRADIC was the first transistorized computer
in the USA, completed in 1954.
The computer was built by J. H. Felker of Bell Labs
for the United States Air Force
while L.C. Brown ("Charlie Brown") was a lead engineer
on the project, which started in 1951. The project initially examined the feasibility of constructing a transistorized airborne digital computer. A second application was a transistorized digital computer to be used in a Navy track-while-scan shipboard radar system. Several models were completed: TRADIC Phase One computer, Flyable TRADIC, Leprechaun (using junction transistor
s in 1956) and XMH-3 TRADIC. TRADIC Phase One was developed to explore the feasibility, in the laboratory, of using transistors in a digital computer that could be used to solve aircraft bombing and navigation problems. Flyable TRADIC was used to establish the feasibility of using an airborne solid-state computer as the control element of a bombing and navigation system. Leprechaun was a second-generation laboratory research transistor digital computer designed to explore the capabilities of new solid-state devices for airborne computers. The TRADIC Phase One computer was completed in January 1954.
The TRADIC Phase One computer has been claimed to be the world's first fully transistorized computer
, ahead of the Mailüfterl
in Austria or the Harwell CADET
in the UK, which were each completed in 1955. In the UK, the Manchester University Transistor Computer demonstrated a working prototype in 1953 which incorporated transistors before TRADIC was operational, although that was not a fully transistorized computer because it used vacuum tubes to generate the clock signal. The 30 watts of power for the 1 MHz clock in the TRADIC was also supplied by a vacuum tube supply because no transistors were available that could supply that much power at that frequency. If the TRADIC can be called fully transistorized while incorporating vacuum tubes, then the Manchester University Transistor Computer should also be, in which case that is the first transistorized computer and not the TRADIC. If neither can be called fully transistorized, then the CADET was the first fully transistorised computer in February 1955.
Flyable TRADIC also incorporated a single high-power output vacuum-tube amplifier to supply clock power to the system. The designers originally devised a system clock using a crystal-controlled transistor oscillator driving a multitude of transistor amplifiers because each transistor was too low powered, but since the phase shift of the amplifiers could not be controlled to the required tolerances this had to be abandoned. So by the same criterion of incorporating vacuum tubes the flyable TRADIC was either not a fully transistorized computer, or followed the after the Manchester University Transistor Computer in 1953. In contrast, the operating requirements for the Flyable TRADIC included performing across a wide temperature range of -55°C (-67°F) to +55°C (+131°F).
The TRADIC Phase One Computer had 684 Bell Labs Type 1734 Type A cartridge transistors and 10,358 germanium point-contact diode
s. The TRADIC was small and light enough to be installed in a B-52 Stratofortress
. It was a general-purpose computer. Programs for the TRADIC Phase One Computer were introduced via a removable plugboard, while the Flyable TRADIC used a Mylar sheet with punched holes — a system reminiscent of punched-card storage. TRADIC could perform a million logical operations every second, close to but not as fast the vacuum tube computers of the day, using its 1 MHz clock. It operated on less than 100 watts of power and it was much more reliable than its vacuum tube
predecessors.
Computer
A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...
in the USA, completed in 1954.
The computer was built by J. H. Felker of Bell Labs
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
for the United States Air Force
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
while L.C. Brown ("Charlie Brown") was a lead engineer
Engineer
An engineer is a professional practitioner of engineering, concerned with applying scientific knowledge, mathematics and ingenuity to develop solutions for technical problems. Engineers design materials, structures, machines and systems while considering the limitations imposed by practicality,...
on the project, which started in 1951. The project initially examined the feasibility of constructing a transistorized airborne digital computer. A second application was a transistorized digital computer to be used in a Navy track-while-scan shipboard radar system. Several models were completed: TRADIC Phase One computer, Flyable TRADIC, Leprechaun (using junction transistor
Junction transistor
Junction transistor might refer to:* Grown-junction transistor* Alloy-junction transistor* Bipolar junction transistor...
s in 1956) and XMH-3 TRADIC. TRADIC Phase One was developed to explore the feasibility, in the laboratory, of using transistors in a digital computer that could be used to solve aircraft bombing and navigation problems. Flyable TRADIC was used to establish the feasibility of using an airborne solid-state computer as the control element of a bombing and navigation system. Leprechaun was a second-generation laboratory research transistor digital computer designed to explore the capabilities of new solid-state devices for airborne computers. The TRADIC Phase One computer was completed in January 1954.
The TRADIC Phase One computer has been claimed to be the world's first fully transistorized computer
Transistor computer
A transistor computer 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 were unreliable. A "second generation" of computers, through the late 1950s and...
, ahead of the Mailüfterl
Mailüfterl
Mailüfterl is an Austrian nickname for the first transistorized computer on the European mainland. The first computers of this kind were TRADIC, Harwell CADET and TX-0.It was built in 1955 at the Vienna University of Technology by Heinz Zemanek...
in Austria or the Harwell CADET
Harwell CADET
The Harwell CADET was the first fully transistorised computer in Europe, and may have been the first fully transistorised computer in the world....
in the UK, which were each completed in 1955. In the UK, the Manchester University Transistor Computer demonstrated a working prototype in 1953 which incorporated transistors before TRADIC was operational, although that was not a fully transistorized computer because it used vacuum tubes to generate the clock signal. The 30 watts of power for the 1 MHz clock in the TRADIC was also supplied by a vacuum tube supply because no transistors were available that could supply that much power at that frequency. If the TRADIC can be called fully transistorized while incorporating vacuum tubes, then the Manchester University Transistor Computer should also be, in which case that is the first transistorized computer and not the TRADIC. If neither can be called fully transistorized, then the CADET was the first fully transistorised computer in February 1955.
Flyable TRADIC also incorporated a single high-power output vacuum-tube amplifier to supply clock power to the system. The designers originally devised a system clock using a crystal-controlled transistor oscillator driving a multitude of transistor amplifiers because each transistor was too low powered, but since the phase shift of the amplifiers could not be controlled to the required tolerances this had to be abandoned. So by the same criterion of incorporating vacuum tubes the flyable TRADIC was either not a fully transistorized computer, or followed the after the Manchester University Transistor Computer in 1953. In contrast, the operating requirements for the Flyable TRADIC included performing across a wide temperature range of -55°C (-67°F) to +55°C (+131°F).
The TRADIC Phase One Computer had 684 Bell Labs Type 1734 Type A cartridge transistors and 10,358 germanium point-contact diode
Diode
In electronics, a diode is a type of two-terminal electronic component with a nonlinear current–voltage characteristic. A semiconductor diode, the most common type today, is a crystalline piece of semiconductor material connected to two electrical terminals...
s. The TRADIC was small and light enough to be installed in a B-52 Stratofortress
B-52 Stratofortress
The Boeing B-52 Stratofortress is a long-range, subsonic, jet-powered strategic bomber operated by the United States Air Force since the 1950s. The B-52 was designed and built by Boeing, who have continued to provide maintainence and upgrades to the aircraft in service...
. It was a general-purpose computer. Programs for the TRADIC Phase One Computer were introduced via a removable plugboard, while the Flyable TRADIC used a Mylar sheet with punched holes — a system reminiscent of punched-card storage. TRADIC could perform a million logical operations every second, close to but not as fast the vacuum tube computers of the day, using its 1 MHz clock. It operated on less than 100 watts of power and it was much more reliable than its vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
predecessors.