TRANSISTOR MUSEUM™  

Historic Transistor Photo Gallery

Photo Essay – Bell Labs Bead Type Point Contact

 

Bell Labs Bead Type Pct Transistor References and Links

 

[1] http://semiconductormuseum.com/PhotoGallery/PhotoGallery_TypeA.htm

This link has photos and references to the early cartridge style point contact transistor.

 

[2] Kleimack, J.J., Shive J.N., Thierfelder W.G., 1958, “Capsulation”, pp. 389-399, in Transistor Technology Vol 1 (Editors: Bridgers, Scaff and Shive). Princeton: D. Van Nostrand.

 

[3] Valdes, L.B. and Thatcher M.L. 1952,Life Tests of Exploratory Development Units”, pp13-33, in Fifth Quarterly Progress Report, 1 May 1952 to 31 July 1952, Department of the Army Project Number 3-19-03-031.

 

[4]  Burcham, N.P. and Horsley G.S. 1958, “Advanced Development of a Hermetically Sealed Point-Contact Transistor”, pp. 427-448, in Transistor Technology Vol 1 (Editors: Bridgers, Scaff and Shive). Princeton: D. Van Nostrand.

 

[5]  Follingstad, H.G., Dennis, F.R. and Kummer, O.  1952, “Formulation of Requirements for Transistor Test Equipment”, Life Tests of Exploratory Development Units”, pp 100-103, in Fifth Quarterly Progress Report, 1 May 1952 to 31 July 1952, Department of the Army Project Number 3-19-03-031.

 

 

                            

 

Photo Essay Commentary

 

The bead type point contact represents a historic and technologically interesting milestone in early transistor development.  Initially undertaken as a potential low cost manufacturing process (plastic beads vs metal cartridges), the early plastic devices proved less reliable than the metal style and the use of plastic bead capsulation was obsolete by the mid 1950s.  

 

 

 

 

 

 

 

Copyright © 2004 by Jack Ward. All Rights Reserved.  http://www.transistormuseum.com/

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