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 (1806 downloads) Popular Download (pdf, 3.60 MB)
pdf 01-Introduction (1658 downloads) Popular Download (pdf, 145 KB)
pdf 02-PictoralSummary (1422 downloads) Popular Download (pdf, 14.36 MB)
pdf 03-DesignPatterns (1258 downloads) Popular Download (pdf, 1.93 MB)
pdf 04-TrunkingPlan (1300 downloads) Popular Download (pdf, 1.32 MB)
pdf 05-Marker (1297 downloads) Popular Download (pdf, 298 KB)
pdf 06-EquipmentArrangements (1178 downloads) Popular Download (pdf, 1.90 MB)
pdf 07-Frames (1275 downloads) Popular Download (pdf, 3.69 MB)
pdf 08-OriginatingDPRegister (1173 downloads) Popular Download (pdf, 340 KB)
pdf 09-TrunkSelection (1203 downloads) Popular Download (pdf, 1.47 MB)
pdf 10-TrafficDistribution (1058 downloads) Popular Download (pdf, 1.33 MB)
pdf 11-Connectors (1145 downloads) Popular Download (pdf, 2.37 MB)
pdf 12-Senders (1173 downloads) Popular Download (pdf, 2.72 MB)
pdf 13-SenderLinkFrames (1126 downloads) Popular Download (pdf, 1.87 MB)
pdf 14-IncomingRegisterLink (1068 downloads) Popular Download (pdf, 1.05 MB)
pdf 15-IncomingRegisterCircuits (1052 downloads) Popular Download (pdf, 1.81 MB)
pdf 16-RegisterAndSenderFrames (959 downloads) Popular Download (pdf, 3.03 MB)
pdf 17-NumberGroupFrame (1064 downloads) Popular Download (pdf, 1.93 MB)
pdf 18-RingingSelection (1213 downloads) Popular Download (pdf, 1.02 MB)
pdf 19-MessageRegisterOperation (1040 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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