The Doctor and his calculators

by James Redin


"A computer like the ENIAC is equipped with 18,000 vacuum tubes and weighs 30 tons, computers in the future may have only 1,000 vacuum tubes and weigh only 1 1/2 tons."

Popular Mechanics, 1949 edition.

Electronic calculators, like computers, were not always small. The LOCI (Logarithmic Calculating Instrument), the first electronic scientific calculator introduced by Wang Laboratories in 1964 had to stand in the floor and supported multiple keyboards attached to them. Dr. An Wang is normally associated with the invention of the ferrite core memory so widely used in early computers, this is a recount of his involvement in the development of the electronic calculators.

It was September of 1949 when An Wang filed his patent application for a "Pulse Transfer Controlling Device." At that time Dr. Wang was not aware on the crucial importance of his invention to the development of digital computers.

His Pulse Transfer Controlling Devices were minuscule toroidal coils with a donut-shaped ferrite core magnetized in one of two possible directions: 0 or 1, the basic units of every bit of information that a computer or electronic calculator can handle. Its permanent but controllable nature made them the ideal substratum to hold the "memory" required by the emerging calculating electronic devices.

On those days Dr. Wang was working for Dr. Howard Aiken at the Harvard Computation Laboratory. It was his first job after obtaining in June 1948 his Ph.D. Degree in Applied Physics at Harvard University. As opposed to MIT policy, Harvard was not interested in promoting, supporting or having control on patents leading to commercial applications, so, following their suggestion, Dr. Wang filed the patent application by himself.

Six years later, in May 17, 1955, the Patent Office issued patent 2,708,722 to Dr. Wang. It took little time for IBM, a company with big stakes on the field, to catch interest on this invention, and after a bitter negotiation IBM bought the patent.

But this was just the beginning for Dr. Wang. An immigrant from China who arrived to the US in 1945 after losing most of his family to the turbulent times of the Japanese invasion, Dr. Wang was a fighter and a free spirited soul who with the impetus of his 27 years, and the creativity of his brilliant mind, had the ideal combination of ingredients to become a perfect entrepreneur and follow the path of the American dream. He founded Wang Laboratories in June 22, 1951 with $600, and his company was officially incorporated in June 30,1955, few weeks after being awarded the first of his 44 patents.

Wang Laboratories was one of the first companies to develop and successfully market electronic calculators. Their first commercial model, the WANG 300 launched in 1965 was their first electronic calculator aimed to compete with the electro-mechanical calculators dominated by companies like Friden and Burroughs, and the early electronic calculators such as the ANITA (A New Inspiration To Arithmetic) manufactured in England by Sumlock Comptometer since 1962, and the Compet (CS-10A) introduced in Japan by Sharp Corp. in 1964.

The WANG 300 was based in the LOCI, a desktop scientific calculator patented by Wang Laboratories in September 17, 1964 (Patent 3,402,285). The LOCI had no resemblance whatsoever to the current small sized high powered calculators. It used a teletype hardcopy device to enter the data and output the results, its main unit had to stand on the floor and supported multiple keyboards

On those days, since multiplier circuits were very expensive, Wang developed an efficient method to compute logarithms based on the circuits used in the LOCI. The WANG 300 used this method to multiply and divide. For example, to compute AxB, the user entered A and pressed the "x" key. At this point the logic converted A into log A, and then, when B was entered the logic converted B into log B, and added (log A + log B) yielding the logarithm of the result. This logarithm was finally converted into the result by finding its antilogarithm value. The result was then displayed. [1]

While the LOCI sold at $6,700 and was more a mini-computer than a calculator, the WANG 300 was a real calculator and sold at $1700. It had about 300 transistors and Instead of a teletype, the WANG 300 used a numerical keyboard and a 10 digit display mounted in a desktop unit. By 1971 its price came down to $600. At that time, about 70% of the revenues generated by Wang Laboratories came from its line of desktop calculators.

Between 1965 and 1969, Wang launched several models of desktop calculators, including the WANG 360, WANG 370 and the WANG 380, The WANG 380 was sold at $3,800. The WANG 700 was announced in 1968 and launched in 1969 to counteract the competition imposed by the Hewlett Packard HP9100 introduced in 1968 and priced in the order of $5000. All the WANG models used the ferrite magnetic-core memory originally invented by Dr. Wang.

Wang calculators were able to generate natural logarithms and exponentials (e^x). These functions were hard-wired into the electronics package, not 'micro-coded' like the trigonometric functions are (the 360 could do trigonometric functions with a special keyboard/display unit that had a sequencer and a diode-ROM array in it, which basically 'pressed keys' in order to perform Sin, Cos, ArcCos, and ArcTan functions.) [2]

Although Wang Laboratories clearly dominated the market of desktop electronic calculators during the second half of the sixties, the appearance in the market of the Integrated Circuits capable to contain all the functions required by a calculator in a single chip, created a fierce price competition in this area, the Doctor, as his employees respectfully called him, decided by 1971 to move into a new direction: word processing and computers. Again, by the end of the 70's, Wang Laboratories dominated the Word Processing market. In 1977 they introduced the VS Wang computer line.

By 1986, Wang Laboratories employed 30,000 people and with sales in the order of 3 billion dollars per year it was at the peak of its success. But its decline was clear at the beginning of the 90's. Part of it can be related to the Doctor's retirement of his active involvement in the company in 1982, and later with his death in 1990 after one year of fight against cancer.

Doctor Wang was also a philanthropist, he believed in sharing his success with social and educational organizations. His contribution to the development of the computer technology and improvement of society will always be remembered.


[1] Bob Otnes. Notes on the Wang 300.

[2] Rick Bensene. Notes on the Wang 360SE.

Eric A. Weiss, "Eloge: An Wang, 1920-1990," IEEE Annals of the History of Computing, Vol. 15, No.1, Pages 60-69, 1993.

Harold A. Layer, "Micro History and Prehistory - An Archaelogical Beginning," IEEE Annals of the History of Computing, Vol. 11, pages 127-130, 1989.

Bobbi A. Kerlin, "INFORMATION and COMMUNICATION TECHNOLOGY. Timeline of Significant Events."

Irene Kim, "Handheld Calculators: Functions at The Fingerprints," Mechanical Engineering Magazine, Vol. 112, No. 1, pages 56-62, Jan 1990.

Copyright James Redin - July 2004 - Revised: January 03, 2010.

X-Number World