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 (1243 downloads) Popular Download (pdf, 3.60 MB)
pdf 01-Introduction (935 downloads) Popular Download (pdf, 145 KB)
pdf 02-PictoralSummary (926 downloads) Popular Download (pdf, 14.36 MB)
pdf 03-DesignPatterns (800 downloads) Popular Download (pdf, 1.93 MB)
pdf 04-TrunkingPlan (811 downloads) Popular Download (pdf, 1.32 MB)
pdf 05-Marker (892 downloads) Popular Download (pdf, 298 KB)
pdf 06-EquipmentArrangements (711 downloads) Popular Download (pdf, 1.90 MB)
pdf 07-Frames (778 downloads) Popular Download (pdf, 3.69 MB)
pdf 08-OriginatingDPRegister (720 downloads) Popular Download (pdf, 340 KB)
pdf 09-TrunkSelection (659 downloads) Popular Download (pdf, 1.47 MB)
pdf 10-TrafficDistribution (661 downloads) Popular Download (pdf, 1.33 MB)
pdf 11-Connectors (706 downloads) Popular Download (pdf, 2.37 MB)
pdf 12-Senders (716 downloads) Popular Download (pdf, 2.72 MB)
pdf 13-SenderLinkFrames (661 downloads) Popular Download (pdf, 1.87 MB)
pdf 14-IncomingRegisterLink (669 downloads) Popular Download (pdf, 1.05 MB)
pdf 15-IncomingRegisterCircuits (660 downloads) Popular Download (pdf, 1.81 MB)
pdf 16-RegisterAndSenderFrames (598 downloads) Popular Download (pdf, 3.03 MB)
pdf 17-NumberGroupFrame (653 downloads) Popular Download (pdf, 1.93 MB)
pdf 18-RingingSelection (770 downloads) Popular Download (pdf, 1.02 MB)
pdf 19-MessageRegisterOperation (611 downloads) Popular Download (pdf, 1019 KB)

New User?

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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