Historic Transistor Photo Gallery   



Shown above is an example of a bulk packaging style used by NU for diodes.  The cardboard packaging unfolds to allow access to the stored diodes.  In the example above, five 1N107 diodes were bulk packaged. Shown below is a section of a 1953 catalogue price list of NU diodes.  The “Union Diodes” type was also known as gold bonded – these were quite a bit more expensive than the standard point contact type.  It is likely than only a limited number of the Union Diodes were sold commercially.     





1N51, 1N107, 1N108  

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Above is a section of a National Union ad from the September 1953 issue of Electronics magazine.  Note that the point contact diodes, such as the 1N51, were labeled with the actual type number: “1N51” for example.  The smaller Union Diode types, such as the 1N107 and 1N108 used color coded bands for type identification.  For example, the color bands brown, black and violet would be used for a 1N107 – brown, black and gray would be used for a 1N108.

Copyright © 2007 by Jack Ward.  All Rights Reserved.