The First Telefunken Transistors

Telefunken in Germany had been producing semiconductor rectifiers for a number of years before they developed transistors for mass production. Launched in 1953, the OC601 and OC602 were alloy junction germanium pnp transistors. Telefunken also developed S (special) versions which had attached copper heatsinks.
These work but are low gain. 
hfe=26, Vf=97mV. hfe=18, Vf=100mV.

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