Folder No. 5 Crossbar book

This 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 manageable. Scanned and converted to PDF by Sam Etler.

Documents

Select Toggle Title Date Download
pdf 00-Contents (1282 downloads) Popular Download (pdf, 3.60 MB)
pdf 01-Introduction (959 downloads) Popular Download (pdf, 145 KB)
pdf 02-PictoralSummary (957 downloads) Popular Download (pdf, 14.36 MB)
pdf 03-DesignPatterns (826 downloads) Popular Download (pdf, 1.93 MB)
pdf 04-TrunkingPlan (838 downloads) Popular Download (pdf, 1.32 MB)
pdf 05-Marker (923 downloads) Popular Download (pdf, 298 KB)
pdf 06-EquipmentArrangements (736 downloads) Popular Download (pdf, 1.90 MB)
pdf 07-Frames (803 downloads) Popular Download (pdf, 3.69 MB)
pdf 08-OriginatingDPRegister (747 downloads) Popular Download (pdf, 340 KB)
pdf 09-TrunkSelection (688 downloads) Popular Download (pdf, 1.47 MB)
pdf 10-TrafficDistribution (684 downloads) Popular Download (pdf, 1.33 MB)
pdf 11-Connectors (732 downloads) Popular Download (pdf, 2.37 MB)
pdf 12-Senders (739 downloads) Popular Download (pdf, 2.72 MB)
pdf 13-SenderLinkFrames (699 downloads) Popular Download (pdf, 1.87 MB)
pdf 14-IncomingRegisterLink (698 downloads) Popular Download (pdf, 1.05 MB)
pdf 15-IncomingRegisterCircuits (690 downloads) Popular Download (pdf, 1.81 MB)
pdf 16-RegisterAndSenderFrames (629 downloads) Popular Download (pdf, 3.03 MB)
pdf 17-NumberGroupFrame (685 downloads) Popular Download (pdf, 1.93 MB)
pdf 18-RingingSelection (811 downloads) Popular Download (pdf, 1.02 MB)
pdf 19-MessageRegisterOperation (641 downloads) Popular Download (pdf, 1019 KB)

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Read the articles under "Introduction" in the black menu bar above.

Recent Contributors

Thanks for new documents from Jim Hurtle, Ed Palazzo, Paul Fassbender, Bruce Patterson, Remco Enthoven, Jon Kolger, Paul Ivester, Len Hicken, Fred Haynes, Kurt Rudolph, Wade ("Kellogg KITT"), the Connections Museum, Rick Walsh, Jeff Lamb, Jeremy Walters, Alan David, Dennis Hock, and Tim Griffin.

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