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 43feb BLR P168 Operator Ad (374 downloads) Popular Download (pdf, 223 KB)
pdf 43jan BLR P113 Telephone Booth (429 downloads) Popular Download (pdf, 672 KB)
pdf 43nov BLR P115 - Steel Handset Parts (372 downloads) Popular Download (pdf, 686 KB)
pdf 44apr BLR P371 Noisy Locations Telephone (379 downloads) Popular Download (pdf, 690 KB)
pdf 44aug BLR P491 Material Replacements (397 downloads) Popular Download (pdf, 194 KB)
pdf 44jan BLR P214 Substitute Materials Booths (481 downloads) Popular Download (pdf, 746 KB)
pdf 44jul BLR P476 Coin Shelves (452 downloads) Popular Download (pdf, 662 KB)
pdf 47oct BLR P375 81A Toner (478 downloads) Popular Download (pdf, 603 KB)
pdf 49Apr BLR P125 555 PBX (761 downloads) Popular Download (pdf, 706 KB)
pdf 49Jan BLR P43 Color 300 Series Sets (504 downloads) Popular Download (pdf, 237 KB)
pdf 49May BLR P165 New 500 (410 downloads) Popular Download (pdf, 763 KB)
pdf 43-45 BLR - Crossbar Toll Reprint (737 downloads) Popular Download (pdf, 14.06 MB)
pdf 41apr BLR p234 Remote Control For Reversible Program Circuits (644 downloads) Popular Download (pdf, 5.82 MB)
pdf 40aug BLR p369 321A Loudspeaking Tel Set and 2A Key Tel System (673 downloads) Popular Download (pdf, 6.73 MB)
pdf 41apr BLR National Defense And The Bell System (762 downloads) Popular Download (pdf, 26.92 MB)
pdf 41apr BLR "No Such Number: Tone for Dial Systems" (1172 downloads) Popular Download (pdf, 2.24 MB)
pdf 74dec BLR P361 - DUE - Detection of Unauthorized Equipment - BLR (1039 downloads) Popular Download (pdf, 479 KB)
pdf 70Oct BLR P259 - Advances in the 1A2 Key Telephone System (1305 downloads) Popular Download (pdf, 6.21 MB)
pdf 66mar BLR - 1A2 Key Telephone System (1694 downloads) Popular Download (pdf, 3.44 MB)
pdf 74nov BLR - p302 812A PBX (1340 downloads) Popular Download (pdf, 9.28 MB)

New User?

Read the articles under "Introduction" in the black menu bar above.

Recent Contributors

Thanks for new documents from 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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