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 27jan BLR P155 Accelerated Testing (1354 downloads) Popular Download (pdf, 923 KB)
pdf 28aug BLR P399 740A PBX (2022 downloads) Popular Download (pdf, 820 KB)
pdf 28oct BLR P44 Dialing Errors (1377 downloads) Popular Download (pdf, 474 KB)
pdf 29dec BLR P162 Lacquering Plating (1428 downloads) Popular Download (pdf, 908 KB)
pdf 29jan BLR P203 Operator Headset (1947 downloads) Popular Download (pdf, 824 KB)
pdf 29nov BLR P113 Telephone Ringing (1579 downloads) Popular Download (pdf, 1.16 MB)
pdf 29oct BLR P73 Toll Calls (1680 downloads) Popular Download (pdf, 778 KB)
pdf 30aug BLR P586 Apparatus Springs (1302 downloads) Popular Download (pdf, 703 KB)
pdf 30dec BLR P175 Apparatus Finishes (1585 downloads) Popular Download (pdf, 812 KB)
pdf 30jun BLR P418 Die Casting (663 downloads) Popular Download (pdf, 838 KB)
pdf 30may BLR P416 Residence PBX - 740-C (779 downloads) Popular Download (pdf, 1007 KB)
pdf 30may BLR P421 Telephone Booth (852 downloads) Popular Download (pdf, 724 KB)
pdf 31jun BLR P470 Insulating Material (684 downloads) Popular Download (pdf, 1.04 MB)
pdf 31may BLR P426 Wear Test (581 downloads) Popular Download (pdf, 1.16 MB)
pdf 31oct BLR P46 Hard of Hearing (581 downloads) Popular Download (pdf, 492 KB)
pdf 32apr BLR P275 Condenser (602 downloads) Popular Download (pdf, 684 KB)
pdf 32aug BLR P421 Inside Wire (608 downloads) Popular Download (pdf, 557 KB)
pdf 32feb BLR P182 Operator Transmitter (575 downloads) Popular Download (pdf, 863 KB)
pdf 32jul BLR P385 Station Ringer (615 downloads) Popular Download (pdf, 669 KB)
pdf 32nov BLR P80 Prorector Block (615 downloads) Popular Download (pdf, 862 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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