Computer Logic Cards

Germanium Alloy Junction Transistor Card From the Early 60s
The 2N404 became the workhorse switching transistor of the computer industry, produced by a number of companies including RCA, GE, TI and Raytheon. Despite advances in silicon, mesa and planar structures, demand for germanium alloy junction transistors continued throughout the 1960s.

This card also has eight Hughes Aircraft HG1012 germanium point contact diodes. HG signified Hughes Glenrothes, so these were UK manufactured. Interestingly the site that manufactured these diodes in the 1960s is now a working Raytheon facility.

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