retroelectro
Fun Fact: The EIA-370 is maintained and reviewed by the JEDEC Committee on Terms, Definitions, and Symbols. They are also responsible for other hits like the JESD88F Dictionary of Terms for Solid State Technology and the JESD100B.01 Terms, Definitions, and Letter Symbols for Microcomputers, Microprocessors, and Memory Integrated Circuits. Both are available as free downloads at JEDEC.org
The character ‘N’ was used for transistors because in the standard for naming vacuum tubes, the ‘N’ meant ‘other’ or ‘none’ and was used mainly for crystals. The third set of characters is assigned consecutively, starting with the number 21. This means that up to 2,201 different registered transistors existed before the release of the 2N2222. Finally, the fourth character is a suffix used to designate revisions to a part, where the part can be substituted for any previous version but not vice versa. The suffix can also be used for devices with special characteristics. The suffix ‘ R ’ is used for diodes meant for reverse polarity but have packages identical to those of a forward-polarity device. Additional suffix characters ‘ S ’ and ‘ L ’ are sometimes used for super-fast-acting diodes. Thoughts on the evolution of this standard The rampant growth of wireless technology in the early twentieth century marks a milestone in civilization. Like most new
technology, a crisis precipitates the change needed to create new generalized standards. World War II brought the issue of unconventional part designators to the forefront. The journey from the DeForest Telegraph Company to the government intervention that created the Radio Corporation of America and consolidated the vast array of patents was pivotal, shaping the industry for all electrical engineers and hobbyists. Consider what the world would be like if the United Wireless Telegraph Company became a successful venture instead of a textbook example of stock fraud during its time. The writer would like to thank the members of the reference desk at the Linda Hall Library and Jack Ward at the Transistor Museum. References [1] "The Founding of RCA and the Relationship Between RCA and Cunningham," [Online]. Available: https://vacuumtubesinc.com/ cunninghampage. [Accessed 06 05 2024]. [2] The Fargo Forum, "A Letter, and What It Means to Holders of United Wireless Telegraph Stock," The Fargo Forum, 11 05 1910. [3] Electrical World, "Investigation of Wireless Business," Electrical World, vol. LV, no. 25, p. 1634, 23 06 1910.
[4] A. C. Streamer, "Electical Manufacturers Geared to War Production," Electrical World, p. 18119, 20 01 1945. [5] J. Ward, "Western Electric 2N23," Transistor Museum, [Online]. Available: http://semiconductormuseum.com/ PhotoGallery/PhotoGallery_2N23.htm . [6] JEDEC, "JEDEC History," [Online]. Available: https://www.jedec.org/about-jedec/jedec- history. [Accessed 29 04 2024]. [7] Microchip, Datasheet: ATtiny1614 / ATtiny1616 / ATtiny1617, 2017. [8] Panasonic Industries, Chip Reistors Array - EXB Type, Panasonic, 2020. [9] "Wireless Companies Merge," New York Times, p. 4, 10 01 1904.
Image Citations
[1-01] DeForest Advertisement (The Saturday Evening Post | March 30, 1929) [1-02] Eveready Advertisement (Circa Early 1930s) [2-01] Advertisement for United Wireless Telegraph Company Stock Citation: Investigation of Wireless Business (Electrical World | June 23, 1910) Citation: Daniels Urges Navy Monopoly of Wireless in America (Santa Ana Register | Santa Ana, Ca | Dec 6, 1918) [2-04] American Radio to Absorb Marconi Co. (New York Sun | New York City, NY | March 23, 1919) [2-05] RCA Logo (Circa 1919) [3-01] Electrical Manufacturers Geared to War Production (Electrical World | Jan 20, 1945) [3-02] RCA Advertising (Circa 1933) [4-01] Cover page of the 1975 JEDEC classic Standard for Designation System for Discrete Semiconductor Devices
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