EFT317

The EFT317 was the first drift (alloy-diffused) transistor of the EFT series made by Electronica in Bucharest; it was suitable for the 10.7 MHz intermediate frequency of FM receivers and for short waves up to 20 MHz [1]. It was used in the self-oscillating RF stage of the Delta S 627 T (1963) and in the Mamaia S 651 T [1]; the French original, the SFT317, was the frequency changer of the Primăvara S 617 T [1].

In 1958 Electronica bought the licence of the French firm COSEM for germanium transistors and diodes; COSEM was then among the leaders, after RCA, at the level of Philips and ahead of Siemens, Telefunken and AEG [1]. Transistor production started at Electronica in 1960, in the halls on Baicului Road [1]. The Romanian transistors kept COSEM’s designations, but with the first letter E instead of S, so SFT became EFT [1]. The first transistors made in Romania were the EFT106, EFT107 and EFT108 for radio and intermediate frequency, and the EFT352, EFT353, EFT121, EFT122 and EFT123 for audio frequency [1].