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The Transistor at 75: The First Makers, Part 7

When I wrote the initial six parts of this series on early transistor makers, I worked from a list of initial companies that made transistors using the early Bell Labs transistor patents. That list of attendees to the April, 1952 Transistor Symposium at Bell Labs came from Bo Lojek’s book, History of Semiconductor Engineering, which is an encyclopedic history of semiconductors. Another book, A History of Engineering and Science in the Bell System: Electronics Technology (1925-1975), published by Bell Labs, says that twenty-six domestic and fourteen foreign licensees, a total of forty companies, attended that symposium. Lojek’s list contained only 34 company names, so his list was clearly incomplete. In addition, some of the company names on Lojek’s list were Bell Labs transistor patent licensees but not symposium attendees. I now know this because my friend Jim Handy, who is the General Director at his memory consultancy Objective Analysis and calls himself “The Memory Guy,” put me in touch with Ed Eckert, the Director of Strategic Industry Standards in the Office of the CTO at Nokia Bell Labs. Eckert introduced me to Sheldon Hochheiser, Corporate Historian at the AT&T Archives and History Center in Warren, New Jersey. Hochheiser quickly produced two original AT&T documents containing the most definitive information about the early transistor makers.

The first AT&T document, a business letter written on Bell Labs stationery and dated October 13, 1982, contains a list of 35 companies that originally licensed the Bell Labs transistor patents during 1952. The second document is a faded, typewritten list of companies and people that attended the Bell Labs Transistor Technology Symposium on April 21 through 29, 1952. That document, created in 1952 when the symposium was held, contains 37 company names, along with the names of their attendees plus four more names of people who attended with no known company affiliation.

Many company names appear on both of these official AT&T lists, but some do not. Some company names on the first list of patent licensees are not on the symposium attendee list, and there are some companies on the attendees list that do not appear on the list of early patent licensees. In the interest of completeness, and because the first six parts of this article series seems to have generated quite a lot of interest, I’ll discuss both lists in this article.

Here’s the list of 1952 Bell Labs transistor patent licensees and the date when they signed a license:

2/1952   Arnold Engineering

2/1952   Brush Electronics

2/1952   Globe-Union

2/1952   Hanovia Chemical and Manufacturing Company

2/1952   T.R. Mallory Company

2/1952   Microwaves Associates

2/1952   Minneapolis-Honeywell

2/1952   Raytheon Manufacturing

2/1952   Radio Receptor Company, Inc

2/1952   Sprague Electric Company

2/1952   Texas Instruments

2/1952   Tung-Sol Electric Company

3/1952   Automatic Electric

4/1952   Automatic Telephone & Electric Company, Ltd

3/1952   The Baldwin Company

9/1952   Bowser, Inc

4/1952   British Thompson-Houston Company, Ltd

4/1952   Bulova Watch Company, Inc

4/1952   Crane Company

4/1952   L.M. Ericsson

4/1952   Felten and Guilleaume Carlfswerk

4/1952   General Electric Company, Ltd (GEC)

4/1952   Hughes Tool Company

3/1952   IBM Corporation

4/1952   IT&T Corporation

4/1952   Lenkurt Electric Company

3/1952   National Cash Register Company

3/1953   National Fabricated Fabrics

4/1952   N.V. Philips

4/1952   Pye, Ltd

3/1952   Radio Development & Research Corp

4/1952   Siemens & Halske

12/1952  Telefunken Gesellschaft

3/1952   Transistor Product Inc

4/1952   English Electric Company, Ltd 

(Note, I believe the date listed for National Fabricated Fabrics should be 1952, not 1953, based on where it appears in the list and because the list shows no other licenses sold in 1953. This list of licensees contained one other typo, showing that Minneapolis-Honeywell bought its license in 1952 and not 1951, which was corrected in handwriting on the AT&T document back in 1985.)

The list of early Bell Labs transistor patent licensees closely matches Lojek’s list of symposium attendees with four exceptions. First, Lojek incorrectly listed English Electric Company and Radio Receptor Company as England Electric Company and Radio Reception Company. These are minor errors and I dealt with those company names in previous articles in this series by showing them correctly in their respective descriptions. I also dealt with the typo that listed T.R. Mallory as P.R. Mallory. It turns out that this typo was not Lojek’s mistake. The same mistake appears on the above list from AT&T. You’ll see the correct spelling in the official 1952 Transistor Symposium attendee list below.

The one name appearing on the above list that does not appear on Lojek’s attendee list is Brush Electronics. As you will see from the official attendee list, this reference is likely to be the Brush Development Company of Cleveland, Ohio. Brush was founded in 1930 to make products based on piezoelectric materials. The company initially manufactured microphones and speakers using piezoelectric elements. The company also got into magnetic recording products and, in 1946, introduced the first tape recorder to be designed and built in the United States. Clevite Corp, also based in Cleveland, purchased Brush in 1952 and subsequently purchased early transistor maker Transistor Products that same year, as discussed in Part 4 of this article series.

Here is the official list of 37 companies attending the 1952 Bell Labs Transistor Symposium in Murray Hill, New Jersey:

Domestic US Companies

  • Automatic Electric
  • Baldwin Company
  • Brush Development Company
  • Bulova Watch
  • Crane Company
  • Federal Telegraph and Radio Corp
  • Federal Telecommunications Laboratories
  • General Electric
  • Globe-Union
  • Hanovia Chemical and Manufacturing Company
  • IBM
  • Lenkurt
  • Microwave Associates
  • Minnesota-Honeywell
  • National Cash Register
  • P.R. Mallory & Company
  • R.M. Arnold Company, Inc
  • Radio Development and Research Corp
  • Radio Receptor Company
  • Raytheon
  • Sprague Electric
  • Texas Instruments
  • Transistor Products
  • Tung-Sol Electric
  • Westinghouse Electric

Foreign Companies

  • Automatic Telephone and Telegraph, Ltd
  • British Thompson-Houston
  • English Electric
  • Ericsson
  • Felten and Guilleaume
  • GEC
  • LCT
  • Philips
  • Pye Ltd
  • Siemens and Halske
  • Standard Telephone & Cables
  • Sueddeutsche Apparatfabrik

This attendee list from the AT&T Archives and History Center allows me to create a more complete catalog of transistor symposium attendees and to correct some errors based on some educated guesses that I made in the previous articles in this series. As I wrote in Part 1 of this series: “…I’m only 95% confident that I have the right list.”

This new information from the AT&T Archives and History Center improves my confidence level, but only for the 37 companies on the above list. Potentially, three companies remain unidentified, but here are the corrections to my original company list, based on this new information:

I incorrectly guessed that Arnold Engineering on Lojek’s list referred to the US Air Force’s Arnold Engineering Development Center (AEDC) at Arnold Air Force Base in Tennessee. Based on these two lists from the AT&T Archives and History Center, it clearly refers to a company founded by Bion J Arnold in 1895 named the Arnold Electric Power Station Company. The company renamed itself in 1905 and became the Arnold Company, which continued to focus on electric power generation. The company then became the Arnold Engineering Company in 1924.

Bion Arnold’s son, R.M. Arnold, worked on magnetic materials for Philco and then joined his father’s company in 1934. The company started developing and manufacturing magnetic materials, including transformer cores and magnets. The AT&T lists show that Arnold Engineering was the first Bell Labs transistor patent licensee and that R.M. Arnold personally attended the 1952 transistor symposium. However, there’s no evidence that Arnold Engineering ever manufactured transistors. Today, the company does business as Arnold Magnetics Technologies and continues to focus on magnetic materials and components.

The General Electric Company in Lojek’s list clearly refers to GEC, the UK’s General Electric Company, and not GE in the US. This was my mistake. I’d thought it was GE in the US, which became a major semiconductor manufacturer in the 1950s and 1960s. However, both the patent licensee list and the transistor symposium list show that GEC in the UK is the correct company. I correctly discussed GEC in Part 5 of this series but incorrectly discussed the US company General Electric in Part 3.

Hughes Tool Company (Hughes Aircraft) appears on Lojek’s list and is on the list of early Bell Labs transistor patent licensees, but it’s not on the official symposium attendee list. Hughes started a semiconductor business making germanium diodes and later got into the transistor market, as discussed in Part 3 of this article series.  

International Telephone and Telegraph Corp (IT&T or ITT) appears on Lojek’s list and on the list of initial Bell Labs transistor patent licensees, but not on the list of symposium attendees. Instead, five ITT subsidiaries do appear on the official attendee list. Those subsidiaries are:

  • Federal Telegraph and Radio Corp
  • Federal Telecommunications Laboratory
  • Standard Telephone & Cables in the UK (discussed in Part 5 of this article series)
  • LCT (Laboratoire Central de Télécommunications) in France
  • Süddeutsche Apparatfabrik in Germany

The Federal Telegraph and Radio Corp was founded as the Poulsen Wireless Company in 1909. The company designed and manufactured high-powered radio transmitters for long-distance wireless communications. Lee de Forest, inventor of the vacuum tube triode – which he named the Audion – was an early employee. The US Navy briefly owned the company but was forced by the US Congress to sell it after World War I. There was a merger with the Mackay Companies in 1927, and then ITT bought the entire operation one year later. Federal Telegraph and Radio Corp then operated as an ITT subsidiary.

There’s virtually no online documentation of the Federal Telecommunications Laboratory except for a truly fascinating 38-minute tape recording made by the Institute of Radio Engineers during the grand opening of the lab’s new facility in Palo Alto in December 1956. Based on an interview with Professor Frederick E. Terman contained within that recording, the Federal Telecommunications Laboratory’s history appears to be closely intertwined with the history of the Federal Telegraph and Radio Corp. The interviews make it appear that the laboratory isn’t really a separate entity. Professor Terman at Stanford University helped many of his engineering students start electronics businesses, most notably Bill Hewlett and Dave Packard who, of course, founded Hewlett-Packard in 1939.

The Laboratoire Central de Télécommunications (LCT) was founded in 1927 as the result of an agreement between ITT and the French Government, which allowed ITT to supply an automatic telephone network for Paris. ITT established the LCT research laboratory as part of that deal. The laboratory was staffed with several hundred researchers recruited from ITT’s international associates, including Bell Telephone in Antwerp and STC in Britain. LTC licensed the Bell Labs transistor patents and started manufacturing point-contact transistors, closely modeled on devices made by Western Electric, followed later by junction transistors.

There’s almost no online mention of Süddeutsche Apparatfabrik (SAF) in Germany, however a sharp-eyed reader named Stephan Spaeth in Germany sent me a link to a Web page about SAF written in German. SAF was founded in 1930 and ITT was one of its parent (or grandparent) companies. The company also appears in a list of reports created by the US War Department’s Bureau of Public Relations after World War II. The reports cover a wide range of industrial companies operating in Germany and Japan during the war and SAF appears to have made selenium rectifiers during that period. By 1950, the company was making germanium point-contact diodes and made some germanium PNP junction transistors starting in 1955. Although the company tried to make the jump to silicon, it was not successful and stopped making transistors by the end of the 1950s.

With that, I’ve done what I can to compile the definitive list of early transistor makers based on the Bell Labs transistor patents. The early transistor history is difficult to compile because it isn’t well documented. The documents that do exist contain errors and typos. The AT&T attendee list contains 37 companies but other documentation from Bell Labs says there were 40 companies at the 1952 transistor symposium, so three companies remain a mystery.

The AT&T list contains four attendee names with unknown associations:

  • S. Kramer
  • L. Keein
  • H. Walker
  • M. Starke

Perhaps the missing three companies are bound to these four names. Time will tell.



Federal Telecommunications Laboratory Opening (tape recording), December 15, 1956.

A History of Transistors in France, Mark Burgess

Rich History of the Arnold Brand



Previous articles in this series:

The Transistor at 75: The First Makers, Part 1

The Transistor at 75: The First Makers, Part 2

The Transistor at 75: The First Makers, Part 3

The Transistor at 75: The First Makers, Part 4

The Transistor at 75: The First Makers, Part 5

The Transistor at 75: The First Makers, Part 6

9 thoughts on “The Transistor at 75: The First Makers, Part 7”

  1. U.S. Patent 879,532 shows Lee DeForest invented the Audion, an intentionally-gassy triode tube for radio-detector use. His circuits lack a D.C. path for the grid, so will not work with a vacuum triode.
    U.S. Patent 1,297,309 shows Harold D. Arnold invented a triode vacuum tube for telephone use.
    U.S. Patent 1,558,436 shows Irving Langmuir invented a triode vacuum tube for radio use.

  2. Traneusee, if you’re trying to campaign that Lee DeForest did not invent the tube triode, you’re probably using the wrong venue because the documentation’s pretty strong and pervasive. That he did not make an excellent triode, because his devices were intentionally gassy, is also not in doubt, and Harold Arnold certainly improved the design through careful research and analysis.

    1. Lee De Forest did invent the tube triode; he just didn’t invent the vacuum-tube triode. I agree this is a nit-picking historical detail in today’s world.

      Steven, I was clarifying your statement “Lee De Forest, inventor of the vacuum tube triode – which he named the Audion” to give proper credit to Arnold and Langmuir for their parts in the invention of the vacuum-tube triode, and to give references that those who are interested in details can look up. I should have included this quote in my first post. My apologies.

    1. Thanks Traneusee. I’m glad you found the articles enjoyable. There’s another 7-part series starting next week about the history of MOS technology.

  3. Thank you for this article. I wish A&T would make these documents publicly available.
    Hughes did make transistors, in a unique axial design, starting with the HA5001-HA5003 types in 1955. They continued making transistors at least into the 1960s.

    1. Thank you for the correction, Jim McAvoy. I’ve confirmed that Hughes did indeed make transistors and found a photo of two Hughes transistors embedded in the Lucite handle of a commemorative letter opener at https://www.chipsetc.com/hughes.html. I’ve corrected Parts 3 and 7 of this series to reflect Hughes more accurately.

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