Vintage British Diodes - Ferranti and STC


Ferranti ZS72 200V silicon diodes and STC CV7476 600V Avalanche diodes
The Ferranti semiconductor division in Oldham, Greater Manchester was a prominent UK semiconductor supplier in the 1960s and 1970s, and produced the world's first programmable logic arrays. Ferranti eventually became Zetex Semiconductors, until acquired by Diodes Incorporated in 2008.
     
STC were the first manufacturer of point contact transistors in the UK, developed at STC in Ilminster, Somerset. STC moved valve (tube) manufacturing from Woolwich to the remote Ilminster in 1940.
Volume semiconductor manufacturing was established in 1956 at the Brimar valve site in Footscray, Kent, eventually becoming part of Nortel before manufacturing ceased in 1993, when IC design was transferred to Nortel in Harlow.

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