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Evolution of CBS Transistor Case Sizes/Shapes

From 1953 (left), 1954 (center), and Final/1955

3” 1/2” X  2” Paper Envelope Packaging

 

 

CBS

2N36 2N37 2N38

 

TYPE

Germanium PNP Alloy Junction Transistor

 

USAGE

General Purpose Audio  

 

DATE INTRODUCED

1953

 

CASE STYLES

Various shapes (see photo)

 

AVAILABILITY

Rare (Limited Production)

HISTORIC NOTES

CBS established a semiconductor manufacturing facility in Lowell Massachusetts soon after purchasing the Hytron vacuum tube manufacturing company, and was producing various germanium devices under the CBS-Hytron label by late 1952.  Products included diodes, point contact and alloy junction transistors.  The 2N36, 2N37 and 2N38 line of transistors were the first “industry-standard/RTMA” numbered transistors from CBS-Hytron, and represent the state-of-the-art in 1952 audio transistor technology.  These devices were crudely made, with manual assembly processes, and the resultant transistors varied widely in performance.  The units were tested, and sorted into different product numbers, based on test results – the 2N36 units were the highest gain, followed by the 2N37 and the 2N38.  Transistor technology was rapidly evolving during the mid 1950s, and a major breakthrough was the development of the hermetically sealed case, which prevented moisture contamination of the internal junctions.  The rightmost 2N38 in the photo above illustrates the first CBS hermetic case style, which obsoleted the two previous case types shown.  Other companies second-sourced this product line, including General Transistor, ETCO, and Radio Receptor.  CBS-Hytron small signal germanium transistor types are quite rare and unique, and represent an important topic in semiconductor history.      

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