A SURVEY OF EARLY POWER TRANSISTORS by Joe Knight GE 1950s SILICON POWER TRANSISTORS
Here now begins the real mystery of GE's first power transistor series. As it turns out, GE actually never registered this new series with JETEC (the "Joint Electron Tube Engineering Council", which handled all tube and semiconductor devices) so even though they had apparently reserved the transistor number series of "2N451-2N454" with JETEC, they never followed up with submitting the official transistor specifications as required by all JETEC members so they could obtain design and spec registration and copy protection. This should have happened NLT 1958 but no record exists in the JETEC files of GE ever doing this and so no JETEC 'Release Numbers' were ever issued either for this series, even though GE had included this series in the Manual's "JETEC Registered" listing. (JETEC 'Release Numbers' were issued when a device(s) was finally registered and made effective as of a certain date.)  However, other transistor manufacturers were also somewhat nonchalant in getting JETEC registration for their own products, such as Transitron.  But this non-action seemed an unusual exception for GE.  Finally and rather abruptly it appears, this new GE power transistor series was deleted in the next GE Fourth Edition Transistor Manual of 1959, almost as if they had never existed (did they ever ?).  No further mention is ever given of these transistors - they were just gone. Upon sorting through my collection of power transistors in preparation for this transistor series, I noticed that one unusual and unidentified output device (see below) did match the unique basing diagram shown for the GE 2N451-454 series.  One can see that this developmental device No. "320" has the same dimensions and unique three straight pins (one being slightly off-set from the other two) and the threaded stud heat-sink attachment base.  So, while matching the housing for the new GE Silicon power transistor, this device actually tests as a functioning Germanium power transistor on a B&K Tester.  Likely, GE was making both germanium and silicon power transistor samples to exactly compare their performance characteristics, using the identical enclosure construction for each. Very correct and scientific of course.
Go To GE Early Power Transistors, Page 6
COPYRIGHT © 2007 by Jack Ward.  All Rights Reserved.  http://www.transistormuseum.com/ Joe Knight Early Power Transistor History – GENERAL ELECTRIC Page 5