David Bakalar Transistor Museum Historic Profile
Recognizing Significant Contributions to 20^th Century Semiconductor History and Technology
Notable Contributions
Shown above is an example of Transitron silicon rectifier technology from the 1950s, in original packaging.  The type 1N250A device above has a 1959 date code, and was rated by Transitron as a medium power rectifier (up to 20 Amps).  The metal case is approx 1 ½” in length and was intended to be stud mounted to a heat sink for maximum   power handling.  Here is early Transitron advertizing text presenting the virtues of silicon rectifiers: “Transitron’s silicon rectifiers meet the long felt need for reliable and efficient power rectification at high temperatures.  Overcoming the basic limitations of selenium, germanium, and vacuum tube, they provide trouble-free operation over wide ambient temperature ranges.  These rugged rectifiers offer major savings in both size and weight in any high temperature application.” Due to the very large scale commercial success of Transitron diode and rectifier technology, the 1950s marked a time of tremendous growth for this pioneering company.  At right is a section of a Sept 1956 recruiting ad for semiconductor technical professionals.  Note that Transitron had grown to over 900 employees in only four years since its founding in 1952.  More Notable Contributions, Page 8
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