Transistor Museum Lecture Hall

 “The Early History of Transistors in Germany”


Rudi Herzog (Continued)


In February of 1952 he introduced three transistors to the public: GT 10, GT 20 and GT 30. In May these transistors were presented to the public during the famous “German Industrial Fair“ which is held each year since 1947 in Hannover and is now known as the Hannover-Fair.  Dr. Rost never mass-produced these devices in quantities, but he was the technological leader for these new developments for the next one or two years.


Later that year one of the bigger electronic companies closed that technological gap to the Rost-laboratory and introduced the VS 200 point-contact-transistor. It was the S.A.F. company located in Nuremberg in the southern part of Germany.  S.A.F. was for “Süddeutsche Apparate Fabrik“ and meant “Southgerman Apparatus Factory“. This company already was a well-known manufacturer of electronic components for the radio-industry, such as condensors, rectifiers etc.




This is a S.A.F. VS200 point contact transistor from early 1953.  Rudi indicates that the company also made  VS220 and VS221 versions, which had higher operating voltages. 



Rudi Herzog (Continued) 


In January the VS 200 was available in quantities. Selected devices of the VS 200 were the VS 220 and 221, which had higher collector voltages of up to 50 volts.   All the other big names of the German electronic scene still had no transistors on their production lines.


One year was gone and at the next Industrial Fair in Hannover in May of 1953 Dr. Rost Labs presented an “oscillator transistor“ which worked up to 10 MHz. It was the G2T.


On the same exhibition TELEFUNKEN showed its first developments of labor samples of transistors to the radio manufacturing industry. Also the SIEMENS & HALSKE  company announced research & development on the semiconductor field. (SIEMENS & HALSKE was the electronic-subsidiary of SIEMENS AG.)  In a house-intern publication in May of 1954 TELEFUNKEN reported about how to use and develop point-contact-transistors.


In October of 1953 the German hearing aid company Wendton offered a hybrid-set with two tubes DF 64 and one transistor. As none of the German manufacturers was able to deliver a suitable device they employed a CK718 of Raytheon to the audio output stage of this “Wensistor 530“ hearing aid.



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