ArticleslgStudy

computer science

Lee Felsenstein

Lee Felsenstein is a computer science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Lee Felsenstein rather than just read about it. In short: Lee Felsenstein (born April 27, 1945) is an American computer engineer who played a central role in the development of personal computers. He was one of the original members of the Homebrew Computer Club and the designer of the Osborne 1, the first mass-produced portable computer.

Lee Felsenstein — main illustration
Lee Felsenstein — illustration

Key takeaways

  • Lee Felsenstein belongs to computer science; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Lee Felsenstein to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Lee Felsenstein from memory before moving on to harder problems.

Reference excerpt

Lee Felsenstein (born April 27, 1945) is an American computer engineer who played a central role in the development of personal computers. He was one of the original members of the Homebrew Computer Club and the designer of the Osborne 1, the first mass-produced portable computer. Before the Osborne, Felsenstein designed the Intel 8080 based Sol-20 computer from Processor Technology, the PennyWhistle modem, and other early "S-100 bus" era designs. His shared-memory alphanumeric video display design, the Processor Technology VDM-1 video display module board, was widely copied and became the basis for the standard display architecture of personal computers. Many of his designs were leaders in reducing costs of computer technologies for the purpose of making them available to large markets. His work featured a concern for the social impact of technology and was influenced by the philosophy of Ivan Illich. Felsenstein was the engineer for the Community Memory project, one of the earliest attempts to place networked computer terminals in public places to facilitate social interactions among individuals, in the era before the commercial Internet.

Life

Felsenstein graduated from Central High School in Philadelphia as a member of class 219. As a young man, Felsenstein was a New Left radical. From October through December 1964, he was a participant in the Free Speech Movement and was one of 768 arrested in the climactic "Sproul Hall Sit-In" of December 2–3, 1964. He also wrote for the Berkeley Barb, one of the leading underground newspapers. He had entered University of California, Berkeley first in 1963, joined the Co-operative Work-Study Program in Engineering in 1964 and dropped out at the end of 1967, working as a Junior Engineer at the Ampex Corporation from 1968 through 1971, when he re-enrolled at Berkeley. He received a B.S. in electrical engineering and computer science from the University of California, Berkeley in 1972. From 1981 to 1983, Felsenstein was employed at the Osborne Computer Corporation. At Osborne, he was the designer of the Osborne 1, the first mass-produced portable computer. He then returned to freelance consulting. In 1992, he joined Interval Research Corporation, where he worked until 2000. From then until 2005, he worked for Pemstar Pacific Consultants, an electronics design and contract manufacturing firm, which was subsequently acquired by Benchmark Electronics. Throughout, he acted as an occasional free-lance consulting designer or worked at his own design firm. Many of his designs were leaders in reducing the costs of computer technologies for the purpose of making them available to large markets. His work featured a concern for the social impact of technology. The Community Memory project, begun as a project of Resource One, Inc. in 1972 and later incorporated in 1977 by Felsenstein with Efrem Lipkin, Ken Colstad, Jude Milhon, and Mark Szpakowski, was one of the earliest attempts to place networked computer terminals in such places as Berkeley supermarkets to attract casual use by persons from all walks of life passing through and facilitate social interactions among non-technical individuals, in the era before the Internet. Felsenstein was influenced in his philosophy by the works of Ivan Illich, particularly Tools for Conviviality (Harper and Row, 1973). This book advocated a "convivial" approach to design which allowed users of technologies to learn about the technology by encouraging exploration, tinkering, and modification. Felsenstein had learned about electronics in much the same fashion, and summarized his conclusions in several aphorisms, to wit – "In order to survive in a public-access environment, a computer must grow a computer club around itself." Others were – "To change the rules, change the tools," and "If work is to become play, then tools must become toys."

Felsenstein was one of the original members of the Homebrew Computer Club, which formed in 1975 in response to the appearance of the Altair 8800 computer kit. With a handy yardstick, Felsenstein "moderated" meetings at the SLAC Auditorium. He was less a chair than a keeper of chaos. In this heyday of the development of the first personal computers, Felsenstein designed the Intel 8080 based Sol-20 computer from Processor Technology, the Micro Expander computer, the Pennywhistle modem, and other early "S-100 bus" era designs. These existed in a market space with early generation hobbyist microcomputers from Altair, IMSAI, Morrow Designs, Cromemco, and other vendors. Felsenstein's shared-memory alphanumeric video display design, the Processor Technology VDM-1 video display module board, was widely copied and became the basis for the standard display architecture of personal computers. Felsenstein was named a "Pioneer of the Electronic Frontier" in 1994 by the Electronic Frontier Foundation, and in 2007, he was given the Editor's Choice Award for Creative Excellence by EE Times magazine. In 1998, Felsenstein founded the Free Speech Movement Archives as an online repository of historical information relating to that event, its antecedents and successors. In 2003, while working with the Jhai Foundation of San Francisco, he designed an open-source telecommunications and computer system for installation in remote villages in the developing world. This system was dubbed "the Pedal-Powered Internet" by The New York Times Magazine due to its reliance on pedal power generation. Installation of the first system in Laos was unsuccessful, but the design has been tested on an Indian reservation in the US and continues in development in India. In 2003, Felsenstein was named a Laureate of The Tech Museum of Innovation (San Jose, California) for this work. Felsenstein is the Founding Sensei of the Hacker Dojo in Mountain View, California, and was featured on a Fox News segment in late 2009 covering the non-profit facility. Felsenstein's older brother is the evolutionary biologist Joseph Felsenstein, a National Academy of Sciences member whose PHYLIP system was one of the earliest examples of bioinformatics. Early versions of PHYLIP were developed on the Sol-20 and Osborne 1, computers designed by Felsenstein. On April 16, 2016, Felsenstein was made a Fellow of the Computer History Museum, "for his influence on the technical and social environment of the early personal computing era."

See also Community Memory Homebrew Computer Club Processor Technology Osborne Computer Corporation Open-source hardware

… excerpt ends here. Continue reading the full article.

Illustrations

Lee Felsenstein illustration
Lee Felsenstein: Processor Technology Sol-20 computer designed by Lee Felsenstein
Processor Technology Sol-20 computer designed by Lee Felsenstein
Lee Felsenstein: Felsenstein at the Vintage Computer Festival, 2005
Felsenstein at the Vintage Computer Festival, 2005

Worked examples

Example 1 — a first encounter with Lee Felsenstein

Start with the simplest possible case. Write down what Lee Felsenstein claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In computer science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Lee Felsenstein before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Lee Felsenstein ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Lee Felsenstein

In research
Lee Felsenstein appears in computer science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Lee Felsenstein in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Lee Felsenstein is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1945 births, American computer scientists, Central High School (Philadelphia) alumni, so understanding it makes those chapters shorter.
In everyday life
Look for Lee Felsenstein outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Lee Felsenstein in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Lee Felsenstein means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Lee Felsenstein out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Lee Felsenstein in simple terms?

Lee Felsenstein (born April 27, 1945) is an American computer engineer who played a central role in the development of personal computers. He was one of the original members of the Homebrew Computer Club and the designer of the Osborne 1, the first mass-produced portable computer.

Why does Lee Felsenstein matter?

Because it connects several computer science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Lee Felsenstein?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Lee Felsenstein.

Tags

  • 1945 births
  • American computer scientists
  • Central High School (Philadelphia) alumni
  • Computer hardware engineers
  • Living people
  • UC Berkeley College of Engineering alumni

Keep exploring