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

Documents

pdf 26Jun BLR P137 Vacuum Tubes Manufacture Popular

By 1938 downloads

Download (pdf, 1.41 MB)

26Jun_BLR_P137_Vacuum_Tubes_Manufacture.pdf

26Jun BLR P137 Vacuum Tubes Manufacture

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 26mar BLR P31 Protective Finish Popular

By 1388 downloads

Download (pdf, 538 KB)

26mar_BLR_p31_Protective_Finish.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 27aug BLR P427 - Dial Tester Popular

By 1348 downloads

Download (pdf, 682 KB)

27aug_BLR_p427_Dial_Tester.pdf

27aug BLR P427 - Dial Tester

Bell Labs Record.  Measuring Dial Speeds. Pendulum Dial Tester. Contributed by Chuck Hensley. 

pdf 27jan BLR P155 Accelerated Testing Popular

By 1330 downloads

Download (pdf, 923 KB)

27jan_BLR_p155_Accelerated_Testing.pdf

27jan BLR P155 Accelerated Testing

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 28aug BLR P399 740A PBX Popular

By 1995 downloads

Download (pdf, 820 KB)

28aug_BLR_p399_740A_PBX.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 28Jul BLR P 363 Non Multiple PBX 551A 551B Popular

By 1658 downloads

Download (pdf, 1.01 MB)

28Jul_BLR_P 363_Non_Multiple_PBX_551A_551B.pdf

28Jul BLR P 363 Non Multiple PBX 551A 551B

Bell Labs Record.  Contributed by Chuck Hensley.

pdf 28oct BLR P44 Dialing Errors Popular

By 1345 downloads

Download (pdf, 474 KB)

28oct_BLR_p44_Dialing_Errors.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 29Apr BLR P 331 Cordless Switchboard 506A Popular

By 1649 downloads

Download (pdf, 1.15 MB)

29Apr_BLR_P 331_Cordless_Switchboard_506A.pdf

29Apr BLR P 331 Cordless Switchboard 506A

Bell Labs Record.  Contributed by Chuck Hensley.

pdf 29dec BLR P162 Lacquering Plating Popular

By 1408 downloads

Download (pdf, 908 KB)

29dec_BLR_p162_Lacquering_Plating.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 29Feb BLR P226 Private Branch Exchanges Popular

By 1334 downloads

Download (pdf, 929 KB)

29Feb_BLR_P226_Private_Branch_Exchanges.pdf

29Feb BLR P226 Private Branch Exchanges

Bell Labs Record.  Contributed by Chuck Hensley.

pdf 29jan BLR P203 Operator Headset Popular

By 1913 downloads

Download (pdf, 824 KB)

29jan_BLR_p203_Operator_Headset.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 29Nov BLR P105 New Multiple PBX 605A Popular

By 1405 downloads

Download (pdf, 826 KB)

29Nov_BLR_P105_New_Multiple_PBX_605A.pdf

29Nov BLR P105 New Multiple PBX 605A

Bell Labs Record.  Contributed by Chuck Hensley.

pdf 29nov BLR P113 Telephone Ringing Popular

By 1561 downloads

Download (pdf, 1.16 MB)

29nov_BLR_p113_Telephone_Ringing.pdf

29nov BLR P113 Telephone Ringing

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 29oct BLR P73 Toll Calls Popular

By 1635 downloads

Download (pdf, 778 KB)

29oct_BLR_p73_Toll_Calls.pdf

29oct BLR P73 Toll Calls

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 29Sep BLR P36 Large Capacity PBX 701A Popular

By 1431 downloads

Download (pdf, 1.30 MB)

29Sep_BLR_P36_Large_Capacity_PBX_701A.pdf

29Sep BLR P36 Large Capacity PBX 701A

Bell Labs Record.  Contributed by Chuck Hensley.

pdf 30aug BLR P586 Apparatus Springs Popular

By 1289 downloads

Download (pdf, 703 KB)

30aug_BLR_p586_Apparatus_Springs.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 30dec BLR P175 Apparatus Finishes Popular

By 1568 downloads

Download (pdf, 812 KB)

30dec_BLR_p175_Apparatus_Finishes.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 30Feb BLR P263 Testing Ringers Dials Popular

By 1560 downloads

Download (pdf, 706 KB)

30Feb_BLR_P263_Testing_Ringers_Dials.pdf

Bell Labs Record.  Contributed by Chuck Hensley.

pdf 30Feb BLR P278 - Dial PBX Residence 750-A Popular

By 1558 downloads

Download (pdf, 719 KB)

30Feb_BLR_P278_Dial_PBX_Residence_750A.pdf

30Feb BLR P278 - Dial PBX Residence 750-A

Bell Labs Record.  750A PBX.  Contributed by Chuck Hensley.

pdf 30Jul BLR P527 Multiplying Subscriber Line No 100 Popular

By 1236 downloads

Download (pdf, 1.18 MB)

30Jul_BLR_P527_Multiplying_Subscriber_Line_No_100.pdf

30Jul BLR P527 Multiplying Subscriber Line No 100

Bell Labs Record.  Contributed by Chuck Hensley.

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.

Please send a file to add your name to this list!

Who's online

We have 493 guests online