Folder BLR

See Chuck Hensley's comprehensive index to articles in the BLR in the folder below.  It can be used to locate articles to research, whether found in the TCI LIbrary or elsewhere.

Chuck has offered to scan a limited number of pages from his collection (at his convenience).  Send requests using the "Contact Us" link in the Menu Bar above.

HINT:  Search for "BLR" followed by a topic keyword to find a series of related articles.  Use alphabetic sort to display them in chronological order.  e.g.  BLR PBX  or  BLR Picturephone.

When posted, complete scanned BLR issues from Sept. 1925 - Dec. 1961 were available here:
  https://worldradiohistory.com/Bell_Laboratories_Record_Issue_Key.htm

Categories

Folder BLR Collections
Folder BLR Index

Documents

Select Toggle Title Date Download
pdf 74Jun BLR P181 Vinyl Drop Wire (665 downloads) Popular Download (pdf, 1.20 MB)
pdf 74May BLR P153 50A Attendant Console (1240 downloads) Popular Download (pdf, 2.11 MB)
pdf 74Nov BLR P302 812A PBX - ocr (1259 downloads) Popular Download (pdf, 2.06 MB)
pdf 74Nov BLR P318 - Seeking the Ideal in "Hands-Free" Telephony for Speakerphones (680 downloads) Popular Download (pdf, 2.08 MB)
pdf 74Sep BLR P239 Telephones Go Modular (722 downloads) Popular Download (pdf, 6.89 MB)
pdf 74Sep BLR P253 Key Telephone Modular Panels (952 downloads) Popular Download (pdf, 1.58 MB)
pdf 28Jul BLR P 363 Non Multiple PBX 551A 551B (1447 downloads) Popular Download (pdf, 1.01 MB)
pdf 29Apr BLR P 331 Cordless Switchboard 506A (1559 downloads) Popular Download (pdf, 1.15 MB)
pdf 29Feb BLR P226 Private Branch Exchanges (1247 downloads) Popular Download (pdf, 929 KB)
pdf 29Nov BLR P105 New Multiple PBX 605A (1330 downloads) Popular Download (pdf, 826 KB)
pdf 29Sep BLR P36 Large Capacity PBX 701A (1357 downloads) Popular Download (pdf, 1.30 MB)
pdf 30Feb BLR P263 Testing Ringers Dials (1438 downloads) Popular Download (pdf, 706 KB)
pdf 30Feb BLR P278 - Dial PBX Residence 750-A (1490 downloads) Popular Download (pdf, 719 KB)
pdf 30Jul BLR P527 Multiplying Subscriber Line No 100 (1164 downloads) Popular Download (pdf, 1.18 MB)
pdf 56Aug BLR P302 Small Dial PBX Attendant (380 downloads) Popular Download (pdf, 1.25 MB)
pdf 57Dec BLR P485 Modern Crossbar PBX 756A (646 downloads) Popular Download (pdf, 801 KB)
pdf 61Jun BLR P220 PBX Speeding Calls 756A DSS (401 downloads) Popular Download (pdf, 528 KB)
pdf 62Oct BLR P327 Crossbar CENTREX Service 5Xbar (528 downloads) Popular Download (pdf, 1.72 MB)
pdf 70Aug BLR P195 Data Communications (515 downloads) Popular Download (pdf, 2.48 MB)
pdf 70Oct BLR P259 - Advances in the 1A2 Key Telephone System (732 downloads) Popular Download (pdf, 1.39 MB)

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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