IBM Early Transistors

Early IBM Alloy Junction Transistor
This is an IBM germanium transistor from the 1950s, early package style. IBM were very active in the early days of transistor development and manufacturing, creating the world's largest manufacturing capability by the early 1960s. IBM also contracted companies like TI and Raytheon to produce Alloy Junction transistors for its computers.

This pnp transistor works, hfe=74, Vbe=0.33V.


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