by Mark Ollig
What’s 10 feet high, 3 feet wide, 100 feet in length, operates using approximately 70,000 resisters, 10,000 capacitors, 18,000 vacuum tubes, and miles of wire; and weighs nearly 30 tons?
That’s right, you guessed it: A computational device called an Electronic Numerical Integrator And Computer, otherwise known as the ENIAC.
The ENIAC has been acknowledged as the first fully-operating, all-electronic, digital computing system.
Its historical marker says the ENIAC “signaled the birth of the Information Age.”
This computer was large and U-shaped. The 40 panel bays it was comprised of inhabited a room 30 by 50 feet.
The electricity required to operate the ENIAC was substantial. It used 150-174 kilowatts of power, which was fed directly into it via dedicated power lines.
ENIAC’s design and construction was financed during World War II by the US Army.
In July of 1943, under the secret code name “Project PX,” the building of the ENIAC began in earnest at the University of Pennsylvania’s Moore School of Electrical Engineering.
The computer became fully operational in 1946.
John Mauchly and J. (John) Presper Eckert Jr. were the co-inventors of the ENIAC.
They both filed for a US patent June 24, 1947, and were later granted U.S. patent number 3,120,606.
Mauchly worked more on the side of the hardware and electrical components, such as vacuum tube technologies. There were 10 different types of vacuum tubes used in the ENIAC.
Eckert engineered the project and solved many of its technical problems, including how to get better dependability from the vacuum tubes by operating them at one-quarter their normal power rating.
Arithmetic, memory, and control elements were part of the ENIAC’s operating systems. There were 20 processing registers or “accumulators” used for addition, subtraction, multiplication, division, and square-root problem solving.
According to Eckert, some of the sub-elements of the ENIAC were binary in nature.
During the computer’s testing in 1945, it performed nuclear physics calculations used during the building of the hydrogen bomb.
When the computer was finished being built, it was transported to the Aberdeen Proving Ground in Maryland. It provided “firing tables” for specific trajectories needed to accurately reach intended targets.
At the time, ballistic targeting calculations normally took 12 hours to perform using a mechanical calculator. The ENIAC could perform these calculations in just 30 seconds.
The army also used its computing power for solutions to other ballistic equations, and artillery firing control problems.
Other uses for the ENAIC’s processing capabilities included: weather forecasting, wind-tunnel designs, atomic-energy calculations, and other scientific applications.
Information was input into the computer using IBM punch cards, and the computer could handle 125 cards per minute. The output information was punched onto IBM cards and then printed.
The ENIAC’s personal requirements called for six technicians working three 8-hour shifts, seven days a week to maintain 24-hour a day operation.
Back in the day, yours truly used many spools of rosin-core solder for soldering “jumper wires” to metal terminal posts on the main distribution frame at the telephone company; however, I doubt I did close to the 5 million hand-soldered joints which were needed to connect all the electrical components and wiring inside the ENIAC.
The ENIAC’s programming interface consisted of controlling some 3,000 rotary switches and dozens of cables plugged into sockets. You programmed the computer by adjusting switches and physically plugging cross-connect cables into the correct sockets in order to work the desired computations.
The six original programmers of the ENIAC were: Betty Snyder Holberton, Jean Jennings Bartik, Kathleen McNulty Mauchly Antonelli, Marlyn Wescoff Meltzer, Ruth Lichterman Teitelbaum, and Frances Bilas Spence.
These six pioneers created some of the basic concepts used in modern computer programming.
The existence of the ENIAC was publically announced Feb. 14, 1946; however, “None of us girls were ever introduced . . .we were just programmers,” Antonelli said in 2001.
Information about these six programmers can be found here: http://eniacprogrammers.org.
“An amazing machine, which applies electronic speeds for the first time to mathematical tasks hitherto too difficult and cumbersome for solution,” said The New York Times when writing about the ENIAC in 1946.
In a 1995 Computerworld magazine interview of J. Presper Eckert by Alexander Randall 5th, Eckert talked about how fast the ENIAC was in solving problems.
“A person with a paper and pencil can add two 10-digit numbers in about 10 seconds. With a hand calculator, the time is down to 4 seconds. The ENIAC was the first electronic digital computer and could add those two 10-digit numbers in 0.0002 seconds – that’s 50,000 times faster than a human, 20,000 times faster than a calculator,” Eckert explained.
The computer processing life of the ENIAC ended at 11:45 p.m. Oct. 2, 1955, when it was turned off.
Four of the original 40 panels of the ENIAC are on display at the University of Pennsylvania School of Engineering and Applied Sciences. You can read more about the ENIAC at the website: http://tinyurl.com/bytes-eniac.