Transistor Museum Early Germanium Power Transistor History by Joe Knight BTL Western Electric Page 14

A SURVEY OF EARLY POWER TRANSISTORS

by Joe Knight

THE POWER TRANSISTOR

BELL TELEPHONE LABS AND WESTERN ELECTRIC

Bell Labs and Western Electric supplied component devices, equipment and systems to many military and government agencies all across the country, mostly for defense contractors and military equipment suppliers. These devices were not available to the normal commercial users. One such group of W.E. semiconductor devices were the "GA" series. This is generally understood to stand for 'Government Account'. As the M2012 was being finalized in 1955, work was also progressing on a device called the W.E. GA-52830, a PNP Germanium fused junction power transistor. It was rated at 1/2 watt of dissipation and was designed for broad-band frequencies and high-speed switching and was first released in April of 1955. It is shown below at the left, along with it's cut-open sample below it. It's HF small element construction is very similar to the BTL 2034. However, the housing did not have the stud bolt connection on the bottom but instead the hook-eye leads as on the 2N66 (also from 1955). The GA-52830 was identified as a limited production 'developmental use only' device, meaning it was not cleared for any final product manufacturing - only prototype work. These were made in the newly opened W.E. Laureldale, PA transistor plant, as were all W.E. power transistors at that time.

A newer version W.E. 'GA' Power Transistor was announced in May of 1956. This was called the GA-53242, again a PNP Germanium fused junction device, rated at 1/2 watt and useful for high speed switching and as a core memory driver (up to 2 Mhz, later up to 4 Mhz). This device is shown above on the right along with its cut-open sample below. While it appears virtually identical to the GA-52830, it was not limited to 'developmental' work, so would qualify for production line usage. Much of this type development work for these military/government transistor designs was funded by Signal Corps contracts with Bell Labs.

Go To BTL/Western Electric Early Power Transistors, Page 15

Joe Knight Early Power Transistor History – BTL/WESTERN ELECTRIC Page 14