Stan Frankel


The Story of the Little Computer That Could!


Revised 8/28/2006

Stanley P. Frankel, Unrecognized Genius

Most of this Web site covers the exploits of people who directly contributed to the development of Hewlett-Packard’s desktop calculators and computers. However, a relatively unknown computer pioneer named Stanley Phillips Frankel made exceedingly strong indirect contributions to these developments although he never worked at or consulted for HP. Instead, Frankel worked on the early development of nuclear weapons at the laboratories in Los Alamos, New Mexico. As a post-doc student under J. Robert Oppenheimer in 1942, Frankel along with Eldred Nelson used an electromechanical calculator to run the calculations that indicated that a uranium fission chain reaction would indeed release considerable energy in an exceedingly large explosion and they made the first calculations to determine the critical amount of uranium needed for a fission bomb. Three years later, Frankel ran other sorts of calculations on ENIAC, the world’s first electronic computer, which laid the computational groundwork for developing thermonuclear (hydrogen) weapons.

Stanley P. Frankel
Photo from IRE Transactions on Electronic Computers
September, 1959

This theoretical work caused Frankel to invent computational techniques that drove the rapid development of computers immediately following World War II. The work also infected Frankel with “the computer disease” (a term coined by the famous Nobel-winning physicist Richard Feynman specifically for Frankel). Frankel became enraptured with computers but he was cruelly cut off from the main force driving advanced computer development (weapons research) when he lost his security clearance during the Red scare of the early 1950s, just as the development of digital computers really started to take off.

In response to this lost opportunity, Frankel became an independent computer consultant. He is directly responsible for designing some significant computers during the 1950s and for indirectly triggering the development of a calculator that was the pre-prototype of HP’s 9100A desktop calculator and the development of the BASIC programming language, which HP used for it’s top-of-the-line desktop calculators and computers throughout the 1970s and into the 1980s.

First There Was Thermal Diffusion

Stanley Frankel was born in Los Angeles in 1919. His first scientific paper appeared in 1940, two years after he earned his BA. The 1-page paper was published while Frankel was a grad student at the University of Rochester in New York. It’s titled “Elementary Derivation of Thermal Diffusion” and it appeared in the Physical Review’s letters section. This paper established Frankel’s expertise in the mathematical modeling of physical phenomena, which will become the bedrock foundation of all theoretical work associated with nuclear weapons development for the next 60 years and beyond. However, in 1940, there’s nothing remotely “nuclear” about Frankel’s work.

In the spring of 1942, Frankel was a post-doc student living on the other side of the US, at the University of California at Berkeley, working for Dr. J. Robert Oppenheimer who is a brilliant theoretical physicist teaching nuclear physics at Berkeley and CalTech. Oppenheimer’s good friend and colleague, Dr. Ernst O. Lawrence, was also a professor at Berkeley and  the world’s foremost authority on cyclotrons. He’s very good at both building ever bigger cyclotrons and at raising the funds to build these machines from both private and government sources.

Because of his work on the cutting edge of nuclear physics and his close association with powerful people in government and industry, Lawrence was heavily involved with the Briggs Advisory Committee on Uranium, which was created by order of President Franklin D. Roosevelt. During 1941, this committee was trying to decide whether or not the development of an atomic bomb was critical to the immediate war effort. Lawrence agitated energetically and repeatedly for the start of a uranium bomb project. He recommended that his friend Oppenheimer be brought in to study the feasibility of building an atomic weapon. The urgency of the topic explosively escalates when the Japanese attack Pearl Harbor on December 7, 1941, thus bringing the United States into World War II.

Oppenheimer, Robert Serber (formerly one of Oppenheimer’s postdoctoral students now at the University of Illinois), and graduate students Eldred Nelson and Stan Frankel performed the calculations on “neutron diffusion” (how neutrons move in a critical assembly of uranium during a nuclear chain reaction) and hydrodynamics (how the energy released by the chain reaction will produce an explosion) that are required to determine the feasibility of an explosive weapon based on uranium fission and the amount of fissionable material needed to build a weapon.

These calculations allowed a group of blue-ribbon theoretical physicists convened by Oppenheimer in June of 1942 to conclude that a fission weapon can be made to work and President Roosevelt subsequently authorizes the creation of the Army’s Manhattan Engineering District (better known as the Manhattan Project) to develop the atomic bomb. In Frankel’s words, the Manhattan Project’s mission was “to put genocide on a paying basis.” However, there’s no evidence that Frankel objected to this mission.

Box 1663

The Manhattan Project charter included the development of an atomic-weapons lab. General Leslie Groves convinces Oppenheimer to become director of the project and Oppenheimer recommends the Los Alamos mesa near Santa Fe, New Mexico for the Lab site because he loves its views of the mountains. Oppenheimer has spent a lot of time in the Los Alamos region of New Mexico and fell in love with the entire area. He’d owned a ranch called “Perro Caliente” (Hot Dog!) located near the Los Alamos mesa since the 1920s.

The Los Alamos weapons lab is constructed during 1943. To the rest of the world, the lab on the mesa is nothing but an anonymous post office box (Box 1663, Santa Fe, New Mexico). Oppenheimer took along many of his associates including Bob Serber, and his doctoral students, including Eldred Nelson and Stan Frankel, to Los Alamos. They became part of the laboratory’s theoretical division (the T division).

Nelson and Frankel had organized a computing service for Lawrence’s cyclotron-based electromagnetic isotope-separation project at Berkeley in 1942. At Los Alamos, they purchased a quantity of mechanical calculators (Marchants, Fridens, and Monroes) like the ones they used at Berkeley to help perform the many calculations required by the project physicists.

Although the Los Alamos physicists performed many calculations on their own, the sheer volume of calculations for the uranium bomb project proved too much, which led to the use of computers (the female kind). The wives of Los Alamos scientists—including Frankel’s wife Mary—were recruited to become, literally, human or “hand” computers that operated the mechanical calculators like industrial production equipment to crank out numbers. These human computers became the T-5 hand-computing group. Nick Metropolis and future Nobel Laureate and expert-on-pretty-much-everything Richard Feynman learned how to fix the mechanical calculators and became the T-5 handymen, working closely with Frankel and Nelson.

Frankel and Nelson did a superb job of organizing the calculations into an assembly line. Frankel’s deep understanding of the mathematical simulation of physical phenomena allowed him to decompose complex calculations into many simpler calculations that were distributed among the human computers. These simpler calculations incur fewer errors and the system worked well, until the humans started to tire of the endless, repetitive calculations.

Before 1943 ended, the endless bomb calculations proved more than the T-5 hand-computing group could handle and the T division decided to automate. There are no electronic computers to be had in 1943 (they didn’t exist yet, except in Iowa) so Los Alamos ordered IBM punched-card tabulation equipment including the IBM model 601 multiplier to help with the calculations. The tabulation equipment could add, subtract, and multiply using IBM punched cards for data input. The IBM punched-card tabulation group was designated T-6 and the tabulating machines were run by enlisted soldiers from the Army’s Special Engineering Detachment.

IBM card-tabulation equipment is brought in to supplement the calculation capabilities of the Los Alamos T-5 group. Photo from Los Alamos Science

Stanley Frankel and Eldred Nelson were put in charge of the IBM-equipped calculations group. Unfortunately, Frankel wasn’t really cut out to lead the group. He reportedly had a temper and verbally abused the soldiers (who were working for peanuts and didn’t have a clue as to why they were running the calculations). Frankel also doesn’t appear to have worked well under pressure and the tensions inevitably rose as the first atomic test (Trinity) loomed.

In addition, Frankel essentially became enraptured with the IBM tabulation equipment. He ignored his supervisory duties (which he didn’t execute well anyway) and focused all of his energy on the wonderful technical abilities of the IBM tabulating machines. He started working on personal projects such as programming the equipment to print nicely formatted trigonometric tables and neglected the bomb calculations.

Hans Bethe, head of the T division, responded to this problem by replacing Frankel with Feynman and Nicholas Metropolis (who would later pioneer the development of computers specifically designed for nuclear weapons development at Los Alamos). Feynman explained to the soldiers that they were helping to develop a weapon to win the war. Life in the calculation group got a lot better and productivity soared. Meanwhile, Frankel was out of a job and needed something else to do. He ended up working on thermonuclear fusion for Edward Teller in Fermi’s F Division.

Teller and the Super

Teller was a brilliant and erratic physicist from Hungary. He had participated in the blue-ribbon symposium Oppenheimer held in June, 1942.  By that time, Teller along with Emil Konopinski had determined that it might be possible to initiate thermonuclear fusion in deuterium (heavy hydrogen) using the energy released by an atomic (fission) bomb. The concept gripped Teller and he could think of little else after that. He named the fusion weapon “The Super” for super-bomb. If Frankel had “the computer disease,” Teller had “the Super” disease.

Until the spring of 1944, Teller worked mostly on fission-related calculations but his heart really belonged to thermonuclear fusion research. Oppenheimer had allowed Teller to continue work on the Super during the early years at Los Alamos but certain discoveries about plutonium made during those early years caused the lab’s research to emphasize a plutonium fission bomb, which required a complicated ignition mechanism called implosion. Teller’s group was supposed to be working on the complex implosion calculations but Teller and his group probably spent half of their time on fusion calculations instead.

Hans Bethe reorganized the T Division in March, 1944 and put Teller in charge of a group that was charged with performing the calculations to produce a mathematical description of the hydrodynamics of implosion. The group included Konopinski, Nick Metropolis, and mathematician John “Johnny” von Neumann. Although Teller successfully determined the equation of state for highly compressed uranium and plutonium that was expected to result from an implosion, Teller wouldn’t supervise the detailed calculations for that equation of state because he wanted to work on the Super. In June, 1944, Teller got Oppenheimer to separate Teller’s group so that Teller to devote himself to the Super. Stanley Frankel joined this group and started working full time on thermonuclear fusion.

By 1945, Teller and his Super group had begun to realize just how immense the job of calculating the Super’s physics was. The complexity of the task was far beyond the reach of mechanical calculators run by a corps of female hand computers. It also proved beyond the reach of the punched-card tabulating machines. However, Johnny von Neumann had another way.

A chance meeting on a train platform in the summer of 1944 between von Neumann and Herman Goldstine led von Neumann to find out about another top secret military project: ENIAC, an electronic computer that was being developed for the army at the Moore School at the University of Pennsylvania in Philadelphia. Goldstine was co-directing the project for the US Army. ENIAC’s mission was to compute more accurate ballistics tables for artillery. The existing hand-computed tables were riddled with errors and the army desperately wanted to automate the generation of tables to weed out the errors. By early 1945, von Neumann started suggesting that ENIAC, when it became operational, might be the answer to the problem of running the Super calculations.

Trinity, Hiroshima, and Nagasaki

The Trinity test went off successfully on July 16, 1945. It proved the design of the plutonium implosion bomb. No such test was needed for the uranium bomb. The physicists had known that the rifle-like uranium bomb design would work since 1942. Two atomic bombs were dropped on Japan in August and World War II ended with Japan’s unconditional surrender on September 1, 1945. Because the war had ended, ENIAC’s primary mission, to compute artillery ballistics tables, became far less important. Consequently, von Neumann was able to arrange for Los Alamos to use the machine even before it was delivered to the army.

On July 16, 1945, the Trinity test verifies that the calculations made by Stanley Frankel in 1942 are correct. Photo from Los Alamos Science

Although ENIAC was not yet fully operational, Frankel and Nick Metropolis had traveled to the Moore School in Pennsylvania in August, 1945 to learn how to program ENIAC and what the machine was capable of doing. Herman Goldstine and his wife Adele gave Frankel and Metropolis a complete ENIAC course including the machine’s theory of operation and the rudimentary programming concepts of the day. Adele Goldstine eventually created the one and only ENIAC programming manual.

The ENIAC of 1945 was not a stored-program computer but an unconnected collection of function units including 20 accumulators that performed addition and subtraction, a multiplier, three function tables, a divider/square-rooter, and so on. These function modules were contained in 40 floor-to-ceiling rack-mount panels and were interconnected using thick patch cords that represented the machine’s “program.” ENIAC was actually a physically configurable electronic equation simulator, not an electronic computer in the modern sense. Even so, it’s not hard to imagine ENIAC capturing technophile Frankel’s imagination.

In his book Eniac, The Triumph and Tragedies of the World’s First Computer, Scott McCartney describes ENIAC:

“What the army got was a thirty-ton monster that filled 1,800 square feetthe size of a three-bedroom apartment in some cities. It had forty different units, including its twenty accumulators, arranged in the shape of a U, sixteen on each side, and eight in the middle, all connected by a ganglion of heavy black cable as thick as a fire hose. It was 1,000 times faster than any numerical calculator, 500 times faster than any existing computing machine. It could perform 5,000 addition cycles per second and to the work of 50,000 people working by hand.”

ENIAC, the world’s first electronic computer, was not programed but wired up to solve a problem. It became operational just in time for Stan Frankel and Nick Metropolis to run the calculations for “the Los Alamos problem,” which sought to find out if a hydrogen bomb was feasible. Photo from Los Alamos Science

The ENIAC “programmer” developed a wiring chart that showed how ENIAC’s function units were to be connected together and switch settings that “loaded” the required constants into the machine’s function tables. A team of technicians then set up the problem-specific wiring and flipped the function-table switches to enter constants associated with the problem. Input data for the problem entered ENIAC by means of IBM punch cards and the ENIAC then performed the simulation it was wired to run. Computed results were punched onto more cards using an IBM card punch.

Parts of ENIAC’s design resembled earlier mechanical calculators in operation. For example, its counters were decimal ring counters instead of the binary counters used in modern computers. Decimal ring counters closely mirror the way mechanical calculators (the Marchant’s, Friden’s, and Monroe’s of the day) use decimal counting wheels to perform their calculations. The reason this fact is significant is that ENIAC’s design will influence the way Frankel, who studies this design very closely in 1945, thinks about computer design over the next 20 years.

The Los Alamos Problem

Frankel and Metropolis returned from the Moore School in the summer of 1945 after learning how to program ENIAC. Together with Frankel’s wife Mary, they started preparing an ENIAC program to perform a most rudimentary Super calculation. It became known as “The Los Alamos Problem.” However, ENIAC was far too small to run the full-fledged simulation required to solve the problem so Frankel and Metropolis oversimplified the simulation. The specifics and certainly the results of The Los Alamos Problem are still classified. However, the calculation grossly oversimplified the question of fusion ignition by reducing the problem to a set of three partial differential equations that modeled the behavior of one-dimensional deuterium-tritium systems with the intent of computing the ignition temperature and related characteristics for such a system. This oversimplified calculation omitted many known physical effects so the model was surely far from accurate.

In fact, Frankel and Metropolis considered the entire effort to be an “exercise” that would simply demonstrate whether or not the problem could be calculated at all. they didn’t expect to get a useful quantitative result from this particular effort.Even so, the problem that ran on ENIAC was the most complex physics calculation ever attempted at the time. The Los Alamos problem started to run on ENIAC in November or December of 1945. Even oversimplified, it flushed many bugs out of the prototype computer because it consumed and exercised more than 95% of the machine’s capacity (99% by some accounts). By January of the next year, the Los Alamos problem had successfully run to completion.

Teller, who had the Super disease, didn’t see the ENIAC results as too simple to be useful. He persuaded Oppenheimer to approve a blue-ribbon panel of current and former Los Alamos scientists to review the ENIAC results in April, 1946. Although the calculations were necessarily simplified and rudimentary, Teller assisted in writing the panel’s conclusion, which stated that a Super bomb could likely be constructed and that it would probably work. Among others, Frankel also signed this report. As with the neutron-diffusion calculations he performed in 1942, Frankel’s ENIAC work helped to further this next stage in nuclear weapons development.

Nick Metropolis
Photo from Los Alamos Science

(Note: Another version of this story, says that the H-bomb calculations proved too complex for ENIAC to handle and that Frankel subsequently ran the problem on a computer at the Eckert-Mauchly Computer Corporation in Philadelphia. However, this version of the story would push the calculations out at least a couple of years because Eckert and Mauchly founded their company on December 22, 1947. This date is later than the April, 1946 review of the ENIAC results and Frankel was no longer working at Los Alamos by 1947. Frankel’s own interviews conducted by Robina Mapstone of the Computer Oral History Project confirm that the calculations did run on ENIAC in late 1945 and early 1946. There has been some conjecture that Frankel and Metropolis ran Monte Carlo calculations (see below) simulating the hydrogen-fusion process on the ENIAC but that seems unlikely because the original ENIAC was not a stored-program machine. Metropolis has stated clearly, in print, that he and Frankel prepared a simplified mathematical model of the thermonuclear reaction that was “realistically calculable” by ENIAC after receiving their training from the Goldstines. Although some limited capability for stored-program operation was later added to ENIAC, the Frankel and Metropolis would have had enough problems just running a the oversimplified, one-dimensional fusion simulation during the ENIAC’s shakedown runs in late 1945 and early 1946. Adding the extra burden of computing random statistical variations to simulate the probabilistic nature of nuclear reactions seems unlikely. However, the ENIAC experience will spur both Frankel and Metropolis to independently start developing computerized implementations of Fermi’s Monte Carlo analysis technique before the decade ends.)
Although the calculations Frankel and Metropolis ran on the ENIAC and the results of those calculations are still classified more than half a century after the fact, the world knows that the H-bomb is feasible through practical demonstration. Both the United States and the USSR exploded thermonuclear bombs in subsequent tests. Frankel and Metropolis published some of their ENIAC results in a paper that appeared in Physical Review in 1947. This paper documents the energies needed to cause heavy atomic nuclei to split and the calculations were done on ENIAC. Significantly, the 1947 Physical Review paper ends with an acknowledgment thanking the Moore School’s ENIAC team for its help in running the calculations for this paper, and those for an unspecified prior problem. That prior problem was obviously the still-classified “Los Alamos problem.”

In February of 1946, after finishing the computations for the Los Alamos H-bomb problem, Frankel and Metropolis had told Goldstine that they planned to take positions at the University of Chicago. The war is over and the physicists are returning to academia after ably serving their country’s defense needs. Chicago is Nick Metropolis’ home town and he wants to return there. Teller, Frankel, Metropolis, and Eldred Nelson joined the University of Chicago’s newly formed Institute for Nuclear Studies (now called the Enrico Fermi Institute), which was created in 1945 after the war ended, to keep together, as much as possible, the team of Chicago-based Manhattan project scientists and engineers.

The Post-War Computer Race and Frankel’s Fall

Just one year later, Frankel is no longer at the Institute for Nuclear Studies. He moved back to his hometown: Los Angeles. Frankel hated Chicago. Eldred Nelson goes with him. Nelson’s wife also hated Chicago. By the end of 1947, Frankel has formed a consultancy with Eldred Nelson and the firm of Frankel & Nelson in Los Angeles consults on problems in applied mathematical physics. Their clients include the electronics division of Hughes Aircraft and Northrup. At Northrup, Frankel and Nelson work on solving navigational errors in missile guidance systems. However, early in 1949, the US Army canceled Frankel’s security clearance because his father had been a Communist. The consulting firm of Frankel & Nelson ceased to exist and Nelson joined Hughes (later, TRW). Nelson recalls this period as a particularly painful time.

(In a few more years, J. Robert Oppenheimer would also be stripped of his security clearance. Both Oppenheimer and Frankel had served their country well during World War II, but both had too closely brushed against the “wrong” causes. McCarthyism and the Red panic would run rampant. When Oppenheimer tried to block development of the H-bomb, he incurred the wrath of the wrong people who decided to remove him from his position of power in the atomic-weapons community. Oppenheimer was “burned at the stake” (in the words of Herbert Grosch). Frankel was treated badly and cast out of the atomic brotherhood, along with several other Los Alamos and Manhattan Project scientists, although Frankel apparently was not publicly barbequed the way that Oppenheimer and many writers and actors from Hollywood were.)

Shortly after Frankel loses his security clearance, Professor Gilbert D. McCann recruits Frankel to become the head of a newly created digital computing group in CalTech’s Engineering Division in Pasadena, California. The job is to provide computing services to CalTech graduate students, much in the same way that Frankel provided these services at Los Alamos. At CalTech, Frankel meets PhD student Bernie Alder, who was working on simulating the interaction of atoms using statistical mechanics and liquid theory. Alder will eventually become one of the first scientists to work at the Lawrence Livermore National Laboratory when it opens in 1952. Frankel started to work with Alder on his PhD thesis problem at Cal Tech. Together, they decide to try using a statistical-analysis technique developed in the 1930s by the famous nuclear physicist Enrico Fermi.

Frankel’s experience with ENIAC in 1945 has spurred him to contemplate the use of electronic computers to explore statistical sampling techniques. Frankel is especially well suited to this line of research because he’s had a long-standing interest in random physical phenomena. He often played solitaire and poker and he contemplated the statistical nature of the card games while he’s playing. He is intensely interested in certain distributions of prime numbers, which he called “lucky numbers,” and he’ll eventually write a paper on the topic.

Further, Frankel’s first brush with computers through the programming of ENIAC alerted him to the fact that computers will alter the way people solve problems. His 1947 paper in Physical Review, written with Nick Metropolis, discusses the use of iterative summation to replace manual integration. Frankel and Metropolis wrote the following footnote in this paper:

In treating this problem with a desk calculator the use of a table of the first elliptic integral in this step would be far easier. However, in setting up the problem for the ENIAC the economy in program controls and programming labor of this procedure seemed to us adequate compensation for the increase in computing time. It seems likely that the use of high speed calculating machines will often effect changes of this kind in the economy of calculating procedures. (Emphasis added.)

Frankel clearly understood the new research vistas made possible by the invention of the computer. He also understood that calculations using computers could take fundamentally different problem-solving approaches so he was clearly primed and ready to apply computers to the non-classical study of statistical physical phenomena when he met Bernie Alder. The analysis technique the two decide to try is now called Monte-Carlo analysis and, since Alder’s and Frankel’s pioneering work, it has become essential to a wide range of scientific and technical work from nuclear weapons development to VLSI chip design.

However, the IBM tabulation equipment that Alder was attempting to use during the late 1940s proved woefully inadequate for Monte-Carlo analysis so Frankel traveled to Manchester, England in the late summer of 1951 (confirmed in the computer logs) where the University of Manchester and Ferranti Ltd. were building a stored-program electronic computer—the Ferranti Mark I, a  commercially re-engineered version of the prototype Manchester Mark I computer built in 1948. Frankel learned how to program the Ferranti machine and he successfully ran Alder’s Monte-Carlo analysis on it. However, Alder’s thesis advisor was a classical physicist and didn’t believe in Fermi’s “unproven” statistical-computation technique. Consequently, he discouraged Alder from publishing his work. As Alder said, if your thesis advisor doesn’t believe in your work, you don’t publish.

Meanwhile, a team of Los Alamos scientists including Nick Metropolis, Arianna Rosenbluth, Marshall Rosenbluth, Augusta Teller, and Edward Teller independently developed Fermi’s Monte-Carlo method into a computerized numerical-analysis technique. They subsequently published a paper titled “Equation of State Calculations by Fast Computing Machines” in the Journal of Chemical Physics during 1953. It is the first published paper on computerized Monte-Carlo analysis to appear. Alder notes that his Monte-Carlo work with Frankel received a footnote in Metropolis’ 1953 paper crediting the two CalTech researchers with simultaneous development of the computerized version of Fermi’s Monte-Carlo technique. Alder and Frankel eventually did publish their work in the Journal of Chemical Physics in 1955, but the earlier paper published by Metropolis and his colleagues became the classic paper that’s widely cited by other researchers today.

The Red Scare Leads to Consulting

Loss of his security clearance also barred Frankel from the inner circles of nuclear and computer research for nuclear weapons development. He stopped attending the annual main event for computer designers called the Joint Computer Conference, which was held throughout the 1950s and 1960s by the IRE (Institute of Radio Engineers), the AIEE (American Institute of Electrical Engineers), and the ACM (Association of Computing Machinery).

Although he had been cast out of this inner circle, Frankel did not stop working with computers. By 1950, Frankel had become one of the most accomplished and experienced computer scientists in the country. While at CalTech, Frankel started designing a simple computer. He wanted to explore the lower limits of what a simple computer might be. While consulting and visiting the electronics division of Hughes Aircraft, Frankel had been encouraged to stuff his pockets with off-spec germanium diodes. Hughes had just started to make these devices and the company had wastebaskets full of functional devices that it couldn’t sell because they failed to meet their advertised specifications. However, they were ideal for digital design.

Frankel called his minimal computer design MINAC. He built a breadboard of the simple computer based on the Hughes germanium diodes and magnetic-drum memory. He’d learned about magnetic-drum memory while visiting ENIAC’s designers, Eckert and Mauchly, in Philadelphia. By that time, Eckert and Maucly had left the Moore School and were working on UNIVAC. Mauchly gave Frankel a lot of advice. Frankel also visited a computer group at the National Bureau of Standards, Raytheon’s computer group, and the Whirlwind group at MIT.

When he returned to CalTech, Frankel found a physics graduate student named James Cass who was very good in the machine shop. Cass hand built a magnetic drum for Frankel while Frankel and his secretary build magnetic heads for the device. By 1954, he’d finished a breadboard of the machine. Librascope, a southern California company located in Glendale, licensed the MINAC design from CalTech (Frankel’s employer), hired Cass to help turn the design into a production-ready product, and hired Frankel as a computer design consultant. Librascope put the MINAC into production, naming it the LGP-30.

The First Personal Computer

The LGP-30 may well be considered the first personal computer. It was an air-cooled, desk-sized, single-user machine. It ran on “only” 1500 Watts of power from a regular 110-volt room outlet and required no special air conditioning. It was also extraordinarily successful. More than 500 LGP-30s were built and sold in the late 1950s and early 1960s, at a time when the sale of one, two, or three units per design was the norm.

This ad for Stan Frankel’s LGP-30 personal computer appeared in the Proceedings of the IRE in May, 1957.

Frankel described the LGP-30’s design in detail in a paper published in the March, 1957 issue of the IRE Transactions on Electronic Computers but the first production LGP-30s were actually built in 1956. Frankel minimized the number of active components needed in the LGP-30 through the extensive use of solid-state diode logic and by placing all of the machine’s memory and registers on a rotating magnetic drum. Consequently, the LGP-30 has only 113 vacuum tubes (and 1450 diodes). At $27,000, it was a relatively inexpensive machine for its day, although Frankel’s goal had been to design an even cheaper machine.

The lineage of the LGP-30 is very confusing. It was first built by Librascope and “LGP” stood for “Librascope General Purpose.” Then General Precision of Glendale, California bought Librascope and “LGP” became “Librascope General Precision.” However, General Precision was just the machine’s manufacturer. The company partnered with the Royal McBee Corporation of Port Chester, New York (a division of Royal Typewriter), which marketed the computer, trained customers, and serviced the machines through its data-processing division. So the advertisements you see in magazines of the day are for Royal McBee LGP-30 computers and the product manuals for the LGP-30 are Royal McBee publications. Librascope survives as Lockheed Martin Librascope. However, the company no longer makes LGP-30s.

A BASIC Contribution

Dartmouth College in Hanover, New Hampshire bought an LGP-30 in 1959. Two Dartmouth researchers, John Kemeny and Thomas Kurtz, used the LGP-30 to develop computer-programming languages that undergraduates could understand, learn, and use. FORTRAN and ALGOL were apparently deemed too complex for the average undergraduate student of the early 1960s. Kemeny and Kurtz developed several simplified programming languages on the LGP-30 including DARSIMCO (Dartmouth Simplified Code), DART, ALGOL 30, SCALP (Self-Contained ALGOL Processor), and DOPE (Dartmouth Oversimplified Programming Experiment). None of these languages became a widespread success but they provided excellent preparation for the main event.

This ad for Stan Frankel’s LGP-30 personal computer appeared in the Proceedings of the IRE in April, 1959.

By 1963, the LGP-30 has become outdated and Dartmouth replaced it with General Electric GE-225 and Datanet-30 computers. Kurtz supervised the development of a timesharing system for the GE computers.  At the same time, Kemeny developed a compiler for the next experimental Dartmouth programming language, the Beginner’s All-purpose Symbolic Instruction Code—or BASIC.

Over the next 20 years, Dartmouth BASIC serves as a foundation for the personal computing world. HP developed its own dialect of BASIC for its minicomputers during the late 1960s and built BASIC interpreters into all of its top-end desktop calculators and computers during the 1970s and 1980s. Indirectly, Frankel’s LGP-30 enabled HP’s rise to the top of the 1970’s personal computer market by creating an early machine environment that encouraged the development of a personal style of computer use. Thanks in part to Frankel’s dream of and work towards the creation of a personal computer, the right companion programming language already existed when HP developed suitable desktop-computer hardware.

A code-compatible, cost-reduced, transistorized version of the LGP-30 called the LGP-21 appeared a few years after the LGP-30 is introduced. According to an interview with Cass, the LGP-21 is a transistorized copy of the LGP-30. The machine’s design uses 460 transistors and about 300 diodes. It runs three times slower than the LGP-30 (an artificial handicap placed on the machine to allow it to be sold for less than the LGP-30, which Librascope continues to offer). The LGP-21 cost much less than the LGP-30 ($16,200 in 1963).

CONAC the Computer and a Microwave Interlude

A little more than two years after the introduction of the LGP-30 (but only one year after he published a paper on the LGP-30’s design), Frankel published a really unusual paper on computer design. It appeared in the September, 1959 issue of IRE Transactions on Electronic Computers. The paper, titled “A Logic Design for a Microwave Computer,” details Frankel’s consulting efforts on behalf of General Electric to develop a computer using microwave devices—traveling-wave tubes and microwave diodes—as digital components. In his paper, Frankel admitted that flip-flops are difficult to create with microwave components. He proposed using delay lines as an alternative for building register storage in a microwave computer. It’s not a new idea. Many early stored-program computers used delay-line memory. Frankel would soon recycle this idea of delay-line storage in his transistorized calculator design.

If he had succeeded, Frankel would have helped GE build a GHz computer thus leapfrogging the industry by 30 to 40 years. However, no such computers appeared and GE eventually sold off its computer hardware business so it’s reasonable to assume that Frankel ran into design problems that were either too expensive to solve or that could not be solved at all. However, the biography that appeared with Frankel’s 1959 article claims that he at least did finish the logic design of the microwave computer. It doesn’t say if the machine was ever built.

Stan, ERMA, and Frankelstan’s Revenge

In 1957, General Electric and IBM competed for a contract from the Bank of America to develop the ERMA (Electronic Recording Method of Accounting) system. GE won. Stanley Frankel did not work on ERMA’s mainframe design but he did develop a small computer for the ERMA system that was to be used as a “paper processor.” This auxiliary processor captured data from newly developed MICR (magnetic ink character recognition) check readers and stored the data on magnetic tape for subsequent processing by ERMA’s mainframe processor, a GE-100 (later renamed the GE-210). Frankel’s auxiliary processor (we would call it an “embedded processor” these days) was considered elegant but it suffered from the lack of a user interface. Programs had to be debugged with an oscilloscope. Consequently, ERMA programmers dubbed the small auxiliary processor  “Frankelstan’s revenge.” Ultimately, Frankel’s design was not used for ERMA. GE added a second GE-100 mainframe to ERMA’s design for other reasons and thus eliminated the need for an auxiliary processor.

The 1959 biography in IRE Transactions on Electronic Computers also provided a list of  other computer designs that Frankel either developed or helped to develop during the 1950s including the CONAC (the Continental Automatic Computer, nicknamed “Connie,” a more advanced, drum-based machine developed by the Continental Oil Company during the period of 1954-1957). Frankel’s Monte-Carlo paper published with Alder in the Journal of Chemical Physics says he’s at the Theoretical Research Group of the Continental Oil Company in Los Angeles by March, 1955 (he’s actually consulting there, helping to develop a computer called CONAC). Oil companies will eventually become the second big users of supercomputers for analysis of seismic data gathered in the search for new oil reserves, following the explosive growth in the use of supercomputers for nuclear weapons design at the US national laboratories.

Throughout the 1950s, Frankel continued to publish scientific and technical papers that list a variety of southern California addresses as a consultant with no company or university affiliation. He also designs a small computer intended for use as an auxiliary document processor for the General Electric 100 and 210 mainframe computers, the M’AC (an “academic” design developed for a Long Beach company named Logical Design), and the NIC-NAC, a desktop calculator.


Frankel’s Last Design

In 1958, as part of a plan to expand from typewriters into a full line of office equipment, the Smith Corona Company (a leading typewriter manufacturer) acquired Marchant (a leading calculator company). Smith Corona marketed Marchant mechanical calculators under the brand name “Smith-Corona Marchant” until 1962 when the entire company adopted that brand name (SCM for short).

Electronic calculators started to appear from companies such as Friden, Sharp, Wang, Mathatronics, IME, and Olympia during the early 1960s. These early machines emulated mechanical calculators—they performed addition, subtraction, multiplication, and division but not transcendental functions. However, even though they performed the same functions and no more, electronic calculators were both faster and quieter than the mechanical versions so the marketplace rapidly adopted the new machines. SCM realized that it needed an electronic calculator in its product line, or it would shortly cede the calculator market to its competitors.

By early 1964, SCM had licensed a Frankel calculator design. Frankel’s calculator design would become SCM’s Cogito 240SR desktop calculator. Prior to engaging Frankel, SCM had hired a very bright electrical engineering graduate from Berkeley named Tom Osborne to help the company enter the electronic era. Osborne studied Frankel’s design and SCM’s production plans for a while and decided that the entire situation didn’t look very good. First, Frankel’s calculator design stored its registers in a recirculating acoustic delay line, similar in function to the rotating magnetic drum he used for the LGP-30, but much slower. The delay line needed milliseconds to recirculate the registers, which was sure to result in slow operation. Further, the design required a large number of crystal diodes that sold for 25 cents each (again like the LGP-30’s design). However, to meet cost targets, SCM planned to use reject diodes that didn’t meet spec (like Frankel’s MINAC, the prototype LGP-30). Osborne felt that plan was a recipe for disaster.

Osborne decided that he didn’t want to work on the Cogito 240SR project any longer. In fact, he believed he could develop a superior calculator design and he proposed this plan to SCM’s management. He even proposed working for free, taking only lab space from SCM until his calculator design was finished. SCM’s management refused the offer, saying it didn’t run the company that way.

SCM weighed the credentials of the freshly minted MSEE from Berkeley against the seasoned computer designer from the Manhattan Project and unsurprisingly decided to bet on Frankel, the veteran. In fact, SCM had already bet on Frankel and had not expected to hear an objection from Osborne. The decision had been made before Osborne even started his analysis. Osborne left SCM and went off on his own, created a brilliant calculator design, got another refusal from SCM, hit the pavement to find a buyer, eventually hooked up with HP, and helped to put HP into the desktop-calculator business.

The Cogito 240SR electronic calculator.
Photo courtesy of Rick Bensene.

SCM developed Frankel’s design without Osborne’s help and put the Cogito 240SR into production by early 1966. The Cogito 240SR was a fully transistorized calculator with a tiny CRT display that showed the contents of three registers. It employed a truly baroque mechanical keyboard that harkened back to the machine’s electromechanical calculator roots and SCM’s typewriter heritage.

Like the LGP-30, the Cogito 240SR used what seems today to be an unusual memory to implement the calculator’s register storage. Instead of a magnetic drum like the LGP-30, the Cogito 240SR used an acoustic delay line to store the 480 bits of memory the calculator requires. The acoustic delay line is a bit-serial storage device and the machine was bit-serial throughout to reduce its cost. Delay-line memories are quaint today, but they were used extensively in early computer designs because core memory was new and expensive, flip-flops required either two tubes or two transistors per bit and were therefore prohibitively expensive, and integrated-circuit memories had yet to be invented.

Osborne was right about the the Cogito 240SR. It was slow. Really slow. In the words of HP’s Director of R&D Barney Oliver, the Cogito 240SR was “a miserable machine, it took forever to do anything.” It was the Cogito 240SR’s use of the slow acoustic delay line for register storage that Osborne had objected to (that and the below-spec diodes). Osborne wanted to use random-access core memory to provide high-speed register storage so that the calculator would complete it’s computations quickly.

The SCM Cogito 240SR may well have been Frankel’s last computer design. If he designed any subsequent machines, the documentation on those later computers is deeply buried. Much of Frankel’s life is poorly documented. I could find only the one photograph of him although most of the other early male members of the Los Alamos team (and their wives) seem amply photographed. The research needed to compose just the few paragraphs about Frankel on this Web page was substantial and represents the assembly of many bits and pieces from more than thirty documents over a month’s time. Research on Frankel’s life would have been nearly impossible before the creation of the World Wide Web and Google’s search engine.

It appears that the Red scare of the early 1950s may have driven Frankel almost completely underground as it did many Hollywood screenplay writers. After 1954, Frankel preferred to work as a paid consultant and avoided joining companies. He published a few papers and a book with Karol Mysels on the topic of soap films in the late 1950s and the 1960s. Frankel’s last published scientific paper (on the thickness measurement of soap films) appears in the September, 1966 issue of the Journal of Applied Physics. His work on soap films appears to be well respected and useful even today but Frankel disappeared from the history of computer development after the introduction of SCM’s Cogito 240SR in 1966. His testimony does appear in the records of the Honeywell vs. Sperry Rand trial that took place during the 1970s.

Frankel’s last published papers give a street address of 411 N. Martel, Los Angeles, California. The house is still standing. Here’s a shot of the house taken in February, 2009.

Frankel House 2-9-09 small

Frankel’s work may be scattered and largely unknown but he had a significant and profound effect on many fields in science and engineering, including computer design, and his dream of a personal computer did come true with the help of his technical legacy. Frankel died in May, 1978. He lived to see the introduction of early microcomputers such as the Altair, Imsai, Radio Shack TRS-80, and Commodore Pet but before the introduction of the IBM PC. Thus Frankel did get to see the early realizations of his dream of truly personal computers.

Special thanks to Rick Bensene for bringing Stan Frankel to my attention and for his efforts in documenting Frankel’s life and his work. Frankel and his story have haunted me ever since.

Information for this Web page came strictly from unclassified, publicly available information sources including personal telephone interviews with Tom Osborne, Eldred Nelson, and:

Alder, B J, Frankel, S P, and Lewinson, V A, Radial Distribution Function Calculated by the Monte-Carlo Method for a Hard Sphere Fluid, The Journal of Chemical Physics, Volume 23, Number 3, March 1955, p 417-419.

Allan, Roy A, A History of the Personal Computer, The People and the Technology, Allan Publishing, London, Ontario, Canada, 2001.

Anderson, Herbert L, “Metropolis, Monte Carlo, and the MANIAC,” Los Alamos Science, Fall 1986, p 96-107.

Bensene, Rick, “SCM Marchant Cogito 240SR Electronic Desktop Calculator,”

Bethe, Hans A, “Observations on the Development of the H-Bomb,” published as Appendix II in the 1989 version of The Advisors, Oppenheimer, Teller, and the Superbomb by Herbert F York, Stanford University Press, 1976, 1989.

Bethe, Hans A, “Coments on the History of the H-Bomb,” Los Alamos Science, Fall, 1982, p 43-53.

Burks, Alice Rowe, Who Invented the Computer? The Legal Battle That Changed Computing History, Prometheus Books, Amherst, NY, 2003.

Conant, Jennet, Tuxedo Park, Simon and Schuster, New York, NY, 2002.

Feynman, Richard, Surely You’re Joking, Mister Feynman!: Adventures of a Curious Character, W W Norton & Company, New York, NY, 1984.

Fitzpatrick, Anne, “Igniting the Light Elements: The Los Alamos Thermonuclear Weapons Project, 1942-1952" PhD dissertation, Virginia Polytechnic Institute and State University, 1999. 

Frankel, S Phillips, “Elementary Derivation of Thermal Diffusion,” Physical Review, Volume 57, Number 7, April 1, 1940, p 661.

Frankel, S and N Metropolis, “Calculations in the Liquid-Drop Model of Fission,” Physical Review, Volume 72, Number 10, November 15, 1947, p 914-925.

Frankel, Stanley P, “Convergence Rates of Iterative Treatments of Partial Differential Equations,” Mathematical Tables and Other Aids to Computation, Volume 4, 1950, p 65-75.

Frankel, S P, “The Logical Design of a Simple General Purpose Computer,” IRE Transactions on Electronic Computers, March 1957, p 5-14.

Frankel, S P, “On the Minimum Logical Complexity Required for a General Purpose Computer,” IRE Transactions on Electronic Computers, December 1958, p 282-284.

Frankel, Stanley P, “A Logic Design for a Microwave Computer,” IRE Transactions on Electronic Computers, September 1959, p 271-276.

Frankel, Stanley P and Karol J Mysels, “On the ‘Dimpling’ During the Approach of Two Surfaces,” Journal of Physical Chemistry, Volume 66, January 1962, p 190-191.

Frankel, Stanley P and Karol J Mysels, “Simplified Theory of Reflectometric Thickness Measurement of Structured Soap and Related Films,” Journal of Applied Physics, Volume 37, Number 10, September 1966, p 3725-3728.

Fritz, W Barkley, “The Women of ENIAC,” IEEE Annals of the History of Computing, Volume 18, Number 3, Fall 1996, p 13-28.

Goldstine, Herman H, The Computer from Pascal to von Neumann, Princeton University Press, Princeton, New Jersey, 1972.

Grosch, Herbert RJ, Computer: Bit Slices from a Life, Third Millennium Books, Novato, CA, 1991.

Groueff, Stephane, Manhattan Project, The Untold Story of the Making of the Atomic Bomb, Little, Brown, and Company, Boston, 1967.

Head, Robert V, ERMA’s Lost Battalion, IEEE Annals of the History of Computing, July-September 2001, Volume 23, Number 3, pages 64-72.

Howes, Ruth H and Caroline L Herzenberg, Their Day in the Sun, Women of the Mahnattan Project, Temple University Press, Philadelphia, PA, 1999.

Jennings, Tom, “Librascope/General Precision LGP-21 Computer,”

Kernan, Donal Mac and Michel Mareschal, “Berni J. Alder, Interview,” SIMU Challenges in Molecular Simulations, Issue 4, Chapter II, Lawrence Livermore Laboratory.

Lee, J A N, “May in Computing History,” Computer, Volume 29, Number 5, May 1996.

Mapstone, Robina, Interview with Dr. Stanley Frankel, October 5, 1972, Computer Oral History Project, Smithsonian Institution.

Mapstone, Robina, Interview with Dr. Stanley Frankel, October 26, 1972, Computer Oral History Project, Smithsonian Institution.

Mapstone, Robina, Interview with James Cass, December 8, 1972, Computer Oral History Project, Smithsonian Institution.

McCartney, Scott, Eniac, The Triumphs and Tragedies of the World’s First Computer, Penguin Putnam, Inc, New York, 1999.

Metropolis, N, J. Howett, and Gian-Carlo Rota, A History of Computing in the 20th Century, Academic Press, New York, NY, 1980.

Metropolis, N, “The Beginning of the Monte Carlo Method,” Los Alamos Science, Special Issue, 1987, p 125-130.

Michael, George, “An Interview with Bernie Alder,”

Thelen, E, “LGP-30,”

“Evolving from Calculators to Computers,”

“Oversight Committee Formed as Lab Begins Research,”

“The Berkeley Summer Study,”

For researchers interested in developing more complete histories of Stanley P. Frankel, the Charles Babbage Institute located at the University of Minnesota has transcripts of his testimony during the Honeywell vs. Sperry Rand trial that occurred during the 1970s. This testimony includes Frankel’s own description of his role in the development of computers during the ENIAC days. The Lemelson Center for the Study of Invention and Innovation at the Smithsonian Institution lists two audio interviews with Frankel and one with James Cass in its collection (on reel-to-reel tapes) and transcripts are available.


HP9825.COM is in no way associated with the Hewlett-Packard Company.

Hewlett-Packard, HP, the HP logos, the HP 9825, and all other product model numbers starting
with HP are all trademarks of the Hewlett-Packard Company and don’t let nobody tell you different!

This site exists strictly for educational purposes. Nothing is for sale here. Substantial material from various issues
of the incomparable Hewlett-Packard Journal appears on this site, by permission of the Hewlett-Packard Company.

All text Copyright 2004 to 2010 - Steve Leibson

[Home] [Prehistoric Times] [The 9100 Project] [Prologues] [The 9825 Projects] [Epilogues]