TRANSISTOR MUSEUM  

Historic Transistor Photo Gallery   

 

 

Transistor Size (5/16”L X 1/8”W X 5/16”H)

Date Code 533 (1955, Week 33)

Packaging-None

Outline of Texas Stamped on Back of Case

 

 

 

TEXAS INSTRUMENTS

900 – 905 SERIES

 

TYPE

Silicon NPN Grown Junction

Low Frequency Amplifier

 

USAGE

Military 

 

DATE INTRODUCED

1954

 

CASE STYLES

Silver Metal

 

AVAILABILITY

Rare (Limited Production)

 

HISTORIC NOTES

Texas Instruments was the first company to offer silicon transistors commercially, announcing the 900 – 905 series of grown junction units in mid-year 1954.  This was several years before other companies were able to produce commercial silicon units, and this early introduction allowed Texas Instruments to gain a large share of the highly profitable military transistor market – silicon units performed reliably at much higher temperatures than germanium units and were in great demand by the US military.  The earliest TI silicon units (as shown in the photo above) are easily identified by the stamped id number (905, for example) on a crude unpainted metal case.  All TI units of this type (early and late) had a stamped outline of the state of Texas on the back of the case.  The first units sold for over $100 each and the cost remained high for many years.  As late as 1965, the Allied Electronics catalogue listed the TI 2N117 type for $8.15, when most comparable germanium units were available in the $1.00 range.  The 2N117 was one of the “follow on” commercial types based on the original 900 series. 

 

Copyright © 2004 by Jack Ward

http://www.transistormuseum.com