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 (447 downloads) Popular Download (pdf, 223 KB)
pdf 43jan BLR P113 Telephone Booth (501 downloads) Popular Download (pdf, 672 KB)
pdf 43nov BLR P115 - Steel Handset Parts (463 downloads) Popular Download (pdf, 686 KB)
pdf 44apr BLR P371 Noisy Locations Telephone (445 downloads) Popular Download (pdf, 690 KB)
pdf 44aug BLR P491 Material Replacements (468 downloads) Popular Download (pdf, 194 KB)
pdf 44jan BLR P214 Substitute Materials Booths (554 downloads) Popular Download (pdf, 746 KB)
pdf 44jul BLR P476 Coin Shelves (525 downloads) Popular Download (pdf, 662 KB)
pdf 47oct BLR P375 81A Toner (595 downloads) Popular Download (pdf, 603 KB)
pdf 49Apr BLR P125 555 PBX (944 downloads) Popular Download (pdf, 706 KB)
pdf 49Jan BLR P43 Color 300 Series Sets (594 downloads) Popular Download (pdf, 237 KB)
pdf 49May BLR P165 New 500 (475 downloads) Popular Download (pdf, 763 KB)
pdf 43-45 BLR - Crossbar Toll Reprint (834 downloads) Popular Download (pdf, 14.06 MB)
pdf 41apr BLR p234 Remote Control For Reversible Program Circuits (717 downloads) Popular Download (pdf, 5.82 MB)
pdf 40aug BLR p369 321A Loudspeaking Tel Set and 2A Key Tel System (752 downloads) Popular Download (pdf, 6.73 MB)
pdf 41apr BLR National Defense And The Bell System (842 downloads) Popular Download (pdf, 26.92 MB)
pdf 41apr BLR "No Such Number: Tone for Dial Systems" (1280 downloads) Popular Download (pdf, 2.24 MB)
pdf 74dec BLR P361 - DUE - Detection of Unauthorized Equipment - BLR (1124 downloads) Popular Download (pdf, 479 KB)
pdf 70Oct BLR P259 - Advances in the 1A2 Key Telephone System (1489 downloads) Popular Download (pdf, 6.21 MB)
pdf 66mar BLR - 1A2 Key Telephone System (1837 downloads) Popular Download (pdf, 3.44 MB)
pdf 74nov BLR - p302 812A PBX (1436 downloads) Popular Download (pdf, 9.28 MB)

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

Recent Contributors

Thanks for new documents from Jim Hurtle, Ed Palazzo, Paul Fassbender, Bruce Patterson, Remco Enthoven, Jon Kolger, Paul Ivester, Len Hicken, Fred Haynes, Kurt Rudolph, Wade ("Kellogg KITT"), the Connections Museum, Rick Walsh, Jeff Lamb, Jeremy Walters, Alan David, Dennis Hock, and Tim Griffin.

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