The next big step of
development took place at the Industrial Fair in April 1954 again: The “Big
Three“ of German electronic industry introduced the first German junction
SIEMENS & HALSKE
presented TF70 and TF71 which were npn-types.
TELEFUNKEN showed the OC601
and OC602 , both pnp-types.
VALVO came up with the OC70
and OC71 . These two pnp-transistors OC70 and OC71 in Germany became as
popular as the CK722 in the US and were used in do-it-yourself applications
to the end of the 1970‘s.
junction-transistors were available in retail by June 1954. In October
1954 VALVO presented the first German power-transistor OC15 ( 4 watts).
Note that in the same month, the world’s first portable transistor radio
TR-1 from Regency came to market in the US.