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 (1206 downloads) Popular Download (pdf, 3.60 MB)
pdf 01-Introduction (911 downloads) Popular Download (pdf, 145 KB)
pdf 02-PictoralSummary (903 downloads) Popular Download (pdf, 14.36 MB)
pdf 03-DesignPatterns (771 downloads) Popular Download (pdf, 1.93 MB)
pdf 04-TrunkingPlan (787 downloads) Popular Download (pdf, 1.32 MB)
pdf 05-Marker (870 downloads) Popular Download (pdf, 298 KB)
pdf 06-EquipmentArrangements (686 downloads) Popular Download (pdf, 1.90 MB)
pdf 07-Frames (748 downloads) Popular Download (pdf, 3.69 MB)
pdf 08-OriginatingDPRegister (696 downloads) Popular Download (pdf, 340 KB)
pdf 09-TrunkSelection (635 downloads) Popular Download (pdf, 1.47 MB)
pdf 10-TrafficDistribution (640 downloads) Popular Download (pdf, 1.33 MB)
pdf 11-Connectors (684 downloads) Popular Download (pdf, 2.37 MB)
pdf 12-Senders (695 downloads) Popular Download (pdf, 2.72 MB)
pdf 13-SenderLinkFrames (645 downloads) Popular Download (pdf, 1.87 MB)
pdf 14-IncomingRegisterLink (653 downloads) Popular Download (pdf, 1.05 MB)
pdf 15-IncomingRegisterCircuits (648 downloads) Popular Download (pdf, 1.81 MB)
pdf 16-RegisterAndSenderFrames (581 downloads) Popular Download (pdf, 3.03 MB)
pdf 17-NumberGroupFrame (633 downloads) Popular Download (pdf, 1.93 MB)
pdf 18-RingingSelection (753 downloads) Popular Download (pdf, 1.02 MB)
pdf 19-MessageRegisterOperation (596 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 Ed Palazzo, Bruce Patterson, Jon Kolger, Paul Ivester, Len Hicken, Paul Fassbender, Fred Haynes, Kurt Rudolph, Wade ("Kellogg KITT"), the Connections Museum, Rick Walsh, Jeff Lamb, Jeremy Walters, Mark Cuccia, Alan David, Harry Joseph, Charlie Terry, Karl Brose, Dennis Hock, Tim Griffin, Remco Enthoven, and Steve Cichorsky.

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