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 1971 downloads

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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 1416 downloads

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26mar_BLR_p31_Protective_Finish.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 27aug BLR P427 - Dial Tester Popular

By 1382 downloads

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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 1356 downloads

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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 2024 downloads

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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 1712 downloads

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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 1379 downloads

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28oct_BLR_p44_Dialing_Errors.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 29Apr BLR P 331 Cordless Switchboard 506A Popular

By 1675 downloads

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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 1431 downloads

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29dec_BLR_p162_Lacquering_Plating.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 29Feb BLR P226 Private Branch Exchanges Popular

By 1351 downloads

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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 1948 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 1421 downloads

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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 1580 downloads

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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 1681 downloads

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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 1449 downloads

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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 1304 downloads

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30aug_BLR_p586_Apparatus_Springs.pdf

Bell Labs Record.  Contributed by Chuck Hensley. 

pdf 30dec BLR P175 Apparatus Finishes Popular

By 1587 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 1579 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 1579 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 1250 downloads

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30Jul_BLR_P527_Multiplying_Subscriber_Line_No_100.pdf

30Jul BLR P527 Multiplying Subscriber Line No 100

Bell Labs Record.  Contributed by Chuck Hensley.

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