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 (1805 downloads) Popular Download (pdf, 3.60 MB)
pdf 01-Introduction (1656 downloads) Popular Download (pdf, 145 KB)
pdf 02-PictoralSummary (1421 downloads) Popular Download (pdf, 14.36 MB)
pdf 03-DesignPatterns (1255 downloads) Popular Download (pdf, 1.93 MB)
pdf 04-TrunkingPlan (1299 downloads) Popular Download (pdf, 1.32 MB)
pdf 05-Marker (1296 downloads) Popular Download (pdf, 298 KB)
pdf 06-EquipmentArrangements (1177 downloads) Popular Download (pdf, 1.90 MB)
pdf 07-Frames (1268 downloads) Popular Download (pdf, 3.69 MB)
pdf 08-OriginatingDPRegister (1172 downloads) Popular Download (pdf, 340 KB)
pdf 09-TrunkSelection (1201 downloads) Popular Download (pdf, 1.47 MB)
pdf 10-TrafficDistribution (1056 downloads) Popular Download (pdf, 1.33 MB)
pdf 11-Connectors (1144 downloads) Popular Download (pdf, 2.37 MB)
pdf 12-Senders (1172 downloads) Popular Download (pdf, 2.72 MB)
pdf 13-SenderLinkFrames (1123 downloads) Popular Download (pdf, 1.87 MB)
pdf 14-IncomingRegisterLink (1067 downloads) Popular Download (pdf, 1.05 MB)
pdf 15-IncomingRegisterCircuits (1051 downloads) Popular Download (pdf, 1.81 MB)
pdf 16-RegisterAndSenderFrames (958 downloads) Popular Download (pdf, 3.03 MB)
pdf 17-NumberGroupFrame (1063 downloads) Popular Download (pdf, 1.93 MB)
pdf 18-RingingSelection (1212 downloads) Popular Download (pdf, 1.02 MB)
pdf 19-MessageRegisterOperation (1039 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 Tim Fox, Andrew Cook, Steph Kerman, Jason Anderson, Doug Duffy, Bruce Patterson, Jeremy Walters, Nick Hunseder, Ed Burnett, Ralph Meyer, Shane Young, David Brown, the Connections Museum, Paul Fassbender, Lou Maffei, Rick Thoensen, Sheila Flory, Tom Hesson, Jim Hurtle, Ed Palazzo, Remco Enthoven, Jon Kolger, Paul Ivester, and Len Hicken.

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