Philco Ge Transistor 2N1500


Small changes having a big impact. Introduced in 1960, Philco had by then improved their etching process to create the thin base layer of their germanium alloy junction transistors. They then replaced the indium electrodes making the emitter and collector junctions with cadmium, giving better thermal dissipation. Due to its speed and thermal performance, it became widely used in computers of the time. These were manufactured by Philco (later Philco-Ford) at their factory in Spring City, PA.

One AI processor chip now has more transistors than the first 25 years at least of the semiconductor industry! 

It works, hfe (gain) is 96, Vf=273mV (so germanium).

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