A SURVEY OF EARLY POWER TRANSISTORS by Joe Knight THE POWER TRANSISTOR BELL TELEPHONE LABS AND WESTERN ELECTRIC
Bell Labs and Western Electric would only go on for a few more years designing and building Power Transistors. The following are the last of the 2N1xxx types, as they were likely coming under increased congressional pressure to let go of their monopolistic manufacturing position in the electronic industry. Besides, other semiconductor firms were making vast headway in power transistors with unheard of power capacity and uhf potential. And Western Electric was moving increasingly towards the world of I.C.'s and micro-chips to run their telephone system of the future, with no tubes and no relays - only with all electronic switching.
A new device called the WE 2N1645 was announced in 1961 which pushed the envelope for high speed switching Power Transistors. This was PNP Germanium Diffused Junction Power Transistor, rated at only 6 watts of dissipation but capable of operating to over 100 MHz. The sample shown at right reflects its TO-38 design. The cut-open 2N1645 sample shows the very small semiconductor wafer needed to achieve these uhf frequencies of over 100 MHz. Go To BTL/Western Electric Early Power Transistors, Page 27
COPYRIGHT © 2008 by Jack Ward.  All Rights Reserved.  http://www.transistormuseum.com/ Joe Knight Early Power Transistor History – BTL/WESTERN ELECTRIC  Page 26