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firms that manufactured transistors for the IBM 1401

Last update March 10, 2018, below.

Below are images of:
Photo of the prevalent Texas Instruments (TI) manufactured alloy-junction germanium transistors, assembled in the IBM-designed-and-built automated alloy-junction germanium transistor manufacturing line, transferred to TI in the late 1950s. Trivia question: How many maps of Texas are inside a 1401? ;-))
the French made/labeled COSEM & RT transistors (from the 729 test frame Marc received from the Netherlands last month.) RT-labeled transistors can also be found in the DE 1401.
COSEM = Compagnie Générale de Semi-conducteurs
The RT transistor photo:
RT = La Radiotechnique, “owned by Philips of the Netherlands”
I don’t recall seeing ingenious IBM-labeled transistors on our 1401 SMS cards before these from the Netherland’s 729 frame. Has anyone else?

Rick Dill’s description of IBM's automated transistor production line
In 1958 on returning to IBM, I found that the development group had built a fully automated factory for producing alloy transistors. It used syntron sonic driven bowls to feed to germanium die, alloy spheres for emitter and collector, stub leads soldered to the spheres during alloying, and the dished base contact washer. These were fed into high purity carbon fixtures, one for each transistor.

Once the assembly was together it went through a hydrogen furnace, after which the transistor was extracted, etched, washed, dried, tested, and then assembled onto a header. The carbon fixture was sent back to be re-used.

This room-sized automated factory could product 40 million transistors a year, which was more than IBM needed.

We shipped the factory to TI with the stipulation that they could use it only for IBM production for a stated number of years.

Here are the links to French transistor history (found searching for “COSEM transistor”):
“History of Transistors in France”:
“Early French Semiconductors”:

Merc Verdiell e-mailed: - Feb 28, 2018
No kidding. They even propose a "proper" French name for transistor, which definitely was sounding way too American: le transitron. Rhymes with the other French inventions: poisson, cochon, electron. Therefore, "my computer uses transistors" becomes the very classy:
"cher Monsieur, mon ordinateur utilise des transitrons". :-)

Robert Garner responded: - Mar 1, 2018

Have you seen this Nov, 2005 IEEE Spectrum article: “How Europe Missed the Transistor:”
Local copy

“In late 1948, shortly after Bell Telephone Laboratories had announced the invention of the transistor, surprising reports began coming in from Europe. Two physicists from the German radar program, Herbert Mataré and Heinrich Welker, claimed to have invented a strikingly similar semiconductor device, which they called the transistron, while working at a Westinghouse subsidiary in Paris.”

Rick Dill - Mar 10, 2018
OK, I have been quoted multiple times in this series. I will finally check in..... this retirement stuff is far too busy for kids to have to put up with and that has only peaked this last fall when my wife retired (at the same age as I did, but about a decade later). More travel than I had many years with IBM and not enough time to accomplish personal projects that seem to move slower at an older age. My classic Porsche is sold to younger friend who has energy to fix it up and skills i wish I still had to enjoy driving it. It is good, but this retirement stuff will kill you if you can't keep up.

I have NO information about IBM's detail contracts with TI, although I am well aware of the automated "factories". I last saw three of them side by side, running full tile for both IBM and also the rest of the world about 1967. TI was interested in low noise transistors (good to get government contracts) and I was interested in the same thing (germanium) for higher speed (electron and hole mobility) and we worked together cooperatively.

On the other hand, IBM did have a research facility at la Gaude (an amazing location outside of town with a view of the Mediterranean sea. I only visited once and wine was available in the cafeteria line. They also had a factory in Corbeil-Essonne , which included some semiconductor production in later years when I visited. There was good connection between French and US academics in the field, so the transistors could have been made there since both IBM and academics were current with each other. IBM was am international company with skills across the globe, even then. There was also pride that would have accelerated sales in Europe or costs there in the 1401 times.

The transistors were the same and had the same roots in the US with the small crowd of guys I worked with ... a rag tag team of engineers without PhD and technicians who were World War II veterans mostly. Engineers, not scientists, and technicians who taught me the tools I needed to build transistors with my fingers in that time. There were far fewer things to hide a technology with than I had in nano-tech patterning a decade ago. Both were fun times, one in semiconductors and the other in magnetic devices you can buy today.

I have no surprise that 1401's in Europe might have been manufactured there and used different component sources, particularly as the 1401 became an early commodity computer.