TRANSISTOR MUSEUM Historic Transistor Photo Gallery
Transistor Size (3/16” Diameter X 1/2”H) Cardboard Box Packaging Stamped “2G” on End Flap “INSP APR 27, 1954” on Side of Box	TRANSISTOR PRODUCTS INC. 2G TYPE Point Contact USAGE Experimental/Switching DATE INTRODUCED 1953/54 CASE STYLES Metal Cartridge Type AVAILABILITY Rare (Prototype – Limited Production)
HISTORIC NOTES Transistors Products Incorporated, a small electronics company located in the Boston area in the early 1950s, was one of the few companies worldwide with the foresight to pay the $25,000 required to Western Electric to license the rights to manufacture transistors, a new and still unproven technology. Within a very few months, TPI was in full scale production, developing a variety of germanium semiconductors, including diodes, point contact transistors and alloy junction transistors. The point contact transistors were manufactured in the style originally developed at Bell Labs, and known as “cartridge type”, a designation which referred to the cartridge shape of the metal tube used to hold the germanium die and two sharp metal contacts required for transistor operation. These were all essentially hand made, with the final performance of the transistor determined by physical manipulation of the points and pulsing with bursts of current. The point contact transistors were then sorted for performance (gain, noise, resistance) and labeled accordingly. The complete TPI point contact offering included types 2A, 2B, 2C, 2D, 2E, 2G, 2H and 2L. A type 2G is shown above - all these were physically identical, with selected performance parameters.
Copyright © 2004 by Jack Ward http://www.transistormuseum.com