The First Commercially Available Transistor in Large Quantities


This is a Raytheon Germanium Alloy Junction transistor from the very early 1950s. The CK718 was the first transistor manufactured in large quantities for commercial applications. 

The socket is for a mini vacuum tube. Raytheon replaced tubes with transistors in hearing aids, one of the first applications for solid state transistors. Raytheon was quick off the mark in the early development of transistors and were first to market with the CK703 point contact transistor in 1948. The CK722 alloy junction transistor was the first widely available transistor and opened up the technology to hobbyists. CK722s were originally lower grade CK718 test rejects.

In the background is part of the original Bell Labs internal voting form for the name of the new device they had invented.

This is a high gain device, Hfe=176, Vf=189mV.

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