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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 20-OperatorConnections (462 downloads) Popular Download (pdf, 180 KB)
pdf 21-ColdCathodeTubeTestSet (502 downloads) Popular Download (pdf, 1.63 MB)
pdf 22-MaintenanceFacilities (430 downloads) Popular Download (pdf, 1.04 MB)
pdf 23-AutomaticMonitor (455 downloads) Popular Download (pdf, 236 KB)
pdf 24-TroubleRecording (863 downloads) Popular Download (pdf, 2.11 MB)
pdf 25-RegisterAndSenderTesting (431 downloads) Popular Download (pdf, 948 KB)
pdf 26-PermanentSignals (497 downloads) Popular Download (pdf, 292 KB)
pdf 27-PulseConversion (435 downloads) Popular Download (pdf, 157 KB)
pdf 28-AlarmSystem (470 downloads) Popular Download (pdf, 965 KB)
pdf 29-InterofficeTransferOfAlarms (464 downloads) Popular Download (pdf, 249 KB)
pdf 30-AMATranslator (461 downloads) Popular Download (pdf, 2.66 MB)
pdf 31-Pretranslation (464 downloads) Popular Download (pdf, 1.28 MB)
pdf 32-TrafficRegisters (418 downloads) Popular Download (pdf, 3.06 MB)

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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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