Recently interest was expressed in this switching system. The Telephone Collectors International (TCI) organization maintains a website with a collection of numerous historical telephony documentation.
Included is "a digital reproduction of a book published by Bell Labs containing a number of articles from 1949 to 1951 that detail most aspects of the No. 5 Crossbar. The articles were all publised in the Bell Laboratories Record. The entire book is 150 pages. Due to the large number of images the book is presented with each article in a separate PDF. This makes the file sizes more maneageable."
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TCI is an excellent organization. E-membership is only $25/year. Their general website is at:
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