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Bell System Books
Jun 17, 2021
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A book kept at the 1XB Originating Trouble Indicator to assist in diagnosing trouble indications. From the Connections Museum, Seattle
Topics: telephone switching, connections museum, txb
Bell System Books
Jun 17, 2021
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A book kept at the Terminating Trouble Indicator to assist in analyzing trouble reports. From the Connections Museum, Seattle
Topics: telephone switching, connections museum, 1xb, crossbar
Bell System Books
May 10, 2021 Bell Telephone Laboratories, Inc.
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Circuit Descriptions -- an adjunct to  System Functional Drawings 10-01 From the Connections Museum, Seattle WA
Topics: telephone switching, 5xb, number 5 crossbar, bell system, connections museum
Bell System Books
Feb 6, 2021
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A reference guide to the perforations on 5XB trouble cards. Contains p/o CD-25805, listing card coordinates and punch meanings.
Topics: telephone switch, 5xb, bell system, 5 xbar, 5 crossbar, telephone museum, connections museum,...
Bell System Books
Oct 8, 2020 American Telephone & Telegraph
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Volume II of the No. 5 Crossbar school book for wire spring relay type circuits.
Topics: 5xb, crossbar, bell system, western electric, telephone switching
Bell System Books
Jul 23, 2020 Western Electric Co.
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Original from telephonecollectors.info Polished it up and made it look not-quite-so-bad.
Topics: telephones, western electric, bell system
Bell System Books
Jul 21, 2020 Bell Telephone Laboratories, Incorporated
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A schoolbook used to teach craftspeople how the No. 5 Crossbar works. From the Connections Museum, Seattle
Topics: 5xb, crossbar, telephone switch, at&t, bell system, bell labs, western electric
Bell System Books
Jul 20, 2020 Bell Telephone Laboratories, Incorporated
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A 5XB Schoolbook, containing Operational Sketches From the Connections Museum, Seattle
Topics: bell system, 5xb, 5 crossbar, telephone switch, western electric, at&t
Bell System Books
Jul 16, 2020 Bell Laboratories
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A schoolbook also used for quick reference by 5XB craftspersons. SEQUENCE CHARTS AND REFERENCE MATERIAL SERVICE FEATURES No. 5 CROSSBAR SYSTEM BELL TELEPHONE LABORATORIES, INCORPORATED SWITCHING SYSTEMS DEVELOPMENT DEPARTMENT 463 WEST ST. NEW YORK, 14 From the Connections Museum, Seattle WA
Topics: crossbar, 5xb, bell system, telephone switching
Bell System Books
Jun 28, 2020 Bell Telephone Laboratories
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A bound compilation of several Bell Labs Record articles pertaining to the No. 5 Crossbar system.
Topics: 5xb, crossbar, telephone switch, connections musuem
Bell System Books
Jun 28, 2020 Bell Telephone Laboratories
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A compendium of Bell System Technical Journal articles concerning the No. 1 Crossbar.
Topics: 1xb, crossbar switch, bell system, connections museum, telephone switch
Bell System Books
Jun 28, 2020 Bell Telephone Laboratories
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Functional Drawings, 3 Volumes From the Connections Museum, Seattle WA
Topics: telephone switching, 5xb, number 5 crossbar, bell system, connections museum
Bell System Books
Jun 28, 2020 New York Telephone
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New York Telephone Instructional Data, multiple volumes. Some are missing from our collection, so this is an incomplete document.
Topics: panel switch, telephone switch, connections museum, bell system
Bell System Books
May 18, 2020 Western Electric, Inc.
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A Western Electric publication detailing the steps in No. 1 Crossbar call completion.
Topics: crossbar, bell system
Community Texts
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A booklet handed out to telephone employees working in Seattle's Kenwood (later Lakeview) central office detailing procedures to be taken if Civil Defense alarms were sounded. From the Connections Museum, Seattle.
Topics: civil defense, telephone safety, atomic age, seattle, at&t, bell system
Bell System Drawings
Jun 28, 2019
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Schematic diagram for the connector circuit in the No. 5 Crossbar MTC From the Connections Museum, Seattle
Topics: 5xb, 5 crossbar, trouble recorder
Bell System Drawings
Jun 28, 2019
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Circuit Description for the connector circuit in the No. 5 Crossbar MTC From the Connections Museum, Seattle
Topics: 5xb, connections museum, 5 crossbar, trouble card recorder
Bell System Drawings
May 16, 2019 AT&T
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Circuit description for the No. 1 Crossbar Subscriber Sender Test frame
Topics: bell system, circuit description, crossbar, sender test frame
Bell System Drawings
May 16, 2019 AT&T
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The purpose of this circuit is to provide means for connecting any of 100 district junctors to any of 100 subscriber senders and to provide means for controlling the establishment of these connections one at a time.
Topics: bell system, circuit description, crossbar, subscriber sender link
Bell System Books
Apr 18, 2019 Bell Telephone Laboratories
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Crossbar Dial System Section III, Part 2: Terminating Circuits Bell Telephone Laboratories, Inc. Systems Development Department 463 West Street New York City
Topics: crossbar, telephone switching, 1xb, bell labs
Bell System Books
Apr 18, 2019 Bell Telephone Laboratories
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Crossbar Dial System Section III, Part 1: Originating Circuits Bell Telephone Laboratories, Inc. Systems Development Department 463 West Street New York City
Topics: crossbar, switching, telephone switching, bell system, 1xb
Bell System Books
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Crossbar Dial System Section II Equipment Arrangement with Traffic and Circuit Functions of Crossbar System Frames Bell Telephone Laboratories, Inc. Systems Development Department 463 West Street New York City
Topics: crossbar, switching, bell system, telephone switching, 1xb
Bell System Practices
Oct 23, 2018
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Bell System Practices Central Office Maintenance Educational Information Issue 2, 5-24-50 AT&TCo Standard Systems Used in the Preparation of Wiring Diagrams From the Connections Museum, Seattle
Topics: bell system, diagrams, wiring diagrams, bsp
Bell System Practices
Oct 23, 2018
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Bell System Practices Central Office Maintenance, General Issue A, January 1962 Pacific Northwest Bell Telephone Co. Revised 9-10-1964 From the Connections Museum, Seattle
Topics: bell system, checking list, bsp
Bell System Practices
Oct 23, 2018 AT&T
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Bell System Maintenance Practices Central Offices Routine Tests and Inspections Issue 1, 8-16-1927 Panel Call Indicator Trunk Circuits No. 1 Office
Topics: bsp, bell system, panel call indicator, panel switch, switchboard
Bell System Practices
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Bell System Practices Central Office Maintenance Educational Information Equipment Engineering General Equipment Requirements Later renumbered to 005-108-111 From the Connections Museum, Seattle
Topics: bell system, schematic conventions, equipment requirements
Bell System Practices
Oct 23, 2018 The Pacific Telephone & Telegraph Co.
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Bell System Practices Central Office Maintenance Educational Information Issue C, 6-1-53
Topics: bell system, relays, theory of relays, pacific telephone and telegraph
Bell System Practices
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Bell System Maintenance Practices Central Offices Routine Tests and Inspections Panel Call Indicator Control Circuits No. 1 Office
Topics: bell system, panel call indicator, switchboard, panel switch
Bell System Books
Oct 16, 2018 Western Electric Company
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Machine Switching Equipment Notes Volume II Reprints of papers used for training purposes by the Engineering Department of the Western Electric Company for the term 1920-21 From the collection of the Connections Museum, Seattle WA
Topics: western electric, machine switching, panel switch, bell system, at&t
Bell System Books
Oct 16, 2018 Western Electric Company
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Fundamentals of Equipment Engineering Educational Bulletin No. 2.50 Issued May, 1937 Reissued October, 1940 Reissued May, 1941 Reissued September 1945 Western Electric Company Hawthorne Works Personell Service Branch Training Department
Topics: western electric, equipment engineering, bell system, telephone switching, telephony
Bell System Books
Sep 8, 2018 Western Electric Co.
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No. 5 Crossbar Dial Telephone System - Sketches Educational Bulletin No. 2.5B-2 Western Electric Company Incorporated Hawthorne Works Central Region Engineering Technical Training Section This bulletin is issued to provide general information concerning the relationship between equipment and frames used in the Crossbar No. 5 Dial Telephone System.
Topics: bell system, 5xb, western electric, telephone switching, dial telephone, number 5 crossbar
Bell System Books
Sep 8, 2018 Western Electric Co.
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No. 5 Crossbar Switching System Volume 1: Equipment Applications Telephone Systems Training  Lesson No. 5B Western Electric Company, Incorporated Central Region Engineering Technical Training Section This lesson is issued to describe in general the application and functions of the equipment in the No. 5 Crossbar Switching System.
Topics: crossbar switch, bell system, western electric, telephone switching, 5xb, 5 crossbar, number 5...
Bell System Practices
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BSP enumerating connections using 6050 and 6051 external keys, for use with 1A, 1A1, 1A2 key systems. 
Topics: bsp, key system, bell system, 1a2
Community Texts
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A souvenir booklet regarding the 1962 World's Fair in Seattle, Washington. The book focuses on the Century 21 Exposition. From the library of the Connections Museum, Seattle WA
Topics: world's fair, world fair, century 21, seattle center, space needle, seattle monorail
Bell System Books
Jun 4, 2018 Western Electric Company
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Machine Switching Equipment Notes Volume I Reprints of papers used for training purposes by the Engineering Department of the Western Electric Company for the term 1920-21 Sketches, illustrations and drawings are located in Volume II From the collection of the Connections Museum, Seattle WA
Topics: western electric, machine switching, panel switch, bell system, at&t
Bell System Documents
May 25, 2018 Bell Telephone Laboratories, Inc.
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A booklet intended for use by central office craftspeople when operating the Master Test Frame of a No. 5 Crossbar switch.  Order as BSP item MP-10700
Topics: 5xb, 5 crossbar, bell labs, master test frame, sender test frame, number 5 crossbar
Bell System Practices
May 25, 2018 American Telephone & Telegraph Company
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BSP 040-510-701 Relays / E, EA, F, H, R, T Types / Requirements and Adjusting Procedures From the collection of the Connections Museum, Seattle WA
Topics: bell system, bsp, relays, relay requirements, bell system practices
Bell System Books
Apr 25, 2018 Bell Telephone Laboratories, inc.
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This is is one of a series of Engineering Reference Data Bulletins containing information on tools and gauges designed by the Bell Telephone Laboratories, for other than Military Applications, and manufactured by the Western Electric Company or by other sup­pliers in accordance with specifications prepared by the Laboratories. It is intended primarily for use by engineers of the Laboratories, and contains information on apparatus which may be rated AT&T Co Standard or A&M Only; codes...
Topics: bell system, bell labs, tools, telephone, telephone switching
Bell System Practices
Apr 7, 2018 Pacific Telephone & Telegraph Co.
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BSP A 804.420 Theory of Relays Issue C - 6/1/1953 The Pacific Telephone & Telegraph Co. Details general theory of relays used in the Bell System From the library of the Connections Museum, Seattle WA
Topics: bell system, at&t, relays, telephone switching, bsp, bell system practices
Bell System Ephemera
Jan 24, 2018 Western Electric Co.
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Western Electric News, March 1925, pages 35-37.  Article by E. D, Hall.  Covers the evolution of the  New   York  City exchange system from manual to Panel switching. The main traffic diagram and the last two photos were quarter page size in the original publication. Scanned at high resolution and enlarged to full page - but the original coarse half-tone screen used in the photos limits the quality that can be gained. Original scan contributed by Steph Kerman to...
Topics: mechanical tandem, new york telephone, bell system, panel sender tandem, panel tandem, machine...
Bell System Books
Jan 17, 2018 Pacific Telephone & Telegraph Co.
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This text accompanied a course in panel machine switching given in Seattle in the early 1920s. The course was given to future switchmen in preparation for the introduction of dial service in March 1923. Some of the text specifically mentions the names of the three offices that were installed: Rainier, Melrose, and West. Some chapters are missing from the original document. This copy was mimeographed, and the text had faded significantly. I have edited this document so the text is higher...
Topics: panel switch, machine switching, dial telephones, seattle, 1920s, 1922, 1923, bell system, panel...
Folkscanomy: Ham and Amateur Radio
Jan 15, 2018 US Army Signal Corps
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January 1943 US Army Signal Corps Radio Sets Front Views Receivers and Transmitters Shows various military radio sets as they appeared when operational. 
Topics: us army, signal corps, radio, wwii, world war ii, us military, military history
Folkscanomy: Ham and Amateur Radio
Jan 15, 2018 RCA
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Radio Apparatus for Amateur and Experimental Use with Instructions for Continuous Wave Operation by Radio Corporation of America, Sales Division September 1, 1921 (Courtesy of the New Jersey Antique Radio Club, 2015)
Topics: rca, radio corporation of america, ham radio, cw, continuous wave, rca catalog, vacuum tubes, rca...
Bell System Ephemera
Jan 15, 2018 Bell Telephone Laboratories, Inc.
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The Use of the Lakatos-Hickman Relay in a Subscriber Sender Case 20878 MM-40-130-179 August 13, 1940 A memorandum written by Claude Shannon for the Bell Telephone Laboratories regarding a new type of relay for central office switching equipment. To the best of my knowledge, this relay was never actually implemented in the PSTN switching plant.
Topics: bell labs, claude shannon, relay logic, telephone switching, bell system, at&t, senders
Bell System Ephemera
Dec 11, 2017 Pacific Telephone & Telegraph Co.
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A binder documenting the open house of Seattle's MAin central office open hours in 1935. Includes newspaper clippings, photos, flyers, and other ephemera. From the collection of the Connections Museum, Seattle.
Topics: telephone, open house, bell system, pacific telephone and telegraph, at&t, telephone office,...
Bell System Books
Nov 2, 2017 Pacific Telephone & Telegraph Co.
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Ed Fox was a panel switchman in Seattle's RAinier/PArkway-2 central office. This is a personal notebook of training sketches and drawings that he saved, and gave to the Connections Museum in the 1980s. Besides the training drawings, this folio also includes BSP A445.002 Banks - Panel Multiple Types. 
Topics: bell system, bsp, western electric, panel switch, telephone switching
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
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Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
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Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
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Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
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Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
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Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
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Connections: An Alternative View of Change, by James Burke
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Topics: james burke, connections, technology
Community Video
Sep 19, 2017 James Burke
movies

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Connections: An Alternative View of Change, by James Burke
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Topics: james burke, connections, technology
Bell System Books
Sep 13, 2017 M.D. Fagen, Bell Telephone Laboratories
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A History of Engineering and Science in the Bell System The Early Years (1875 - 1925) Prepared by Members of the Technical Staff, Bell Telephone Laboratories M.D. Fagen, Editor. Bell Telephone Laboratories, Incorporated
Topics: bell system, history of engineering and science, bell laboratories, at&t
Bell System Books
Sep 7, 2017 Bell Telephone Laboratories, Inc.
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Crossbar Toll Articles reprinted from Bell Laboratories Record, Volumes 22 and 23
Topics: bell labs record, bell laboratories record, xbt, crossbar tandem, crossbar toll, XBT, toll...
Folkscanomy Electronics: Books on Electronics, Circuits and Processors
Sep 7, 2017 William Keister, Alistair E Ritchie, Seth H. Washburn
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From the Preface: This book is not a text on telephone systems. It is concerned rather, with the basic techniques of switching circuit design: techniques which are applicable to digital computers and other complex control systems as well as telephone switching systems. The wiring of this text ... started as a series of lecture notes for using in training new engineers in the Switching Systems Development Department of the Bell Telephone Laboratories. ...Arrangements were [later] made with...
Topics: relays, switching circuits, bell sytem, d. van nostrand company, design switching circuits, relay...
Bell System Books
Sep 1, 2017 Western Electric Co.
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Western Electric Company Instructional Bulletin No. 409 The 6-B transmitter is a 1kW AM radio transmitter developed by Bell Laboratories and manufactured by Western Electric. From the library at the Connections Museum, Seattle WA
Topics: western electric, bell labs, radio transmitter, am radio, 6-b radio transmitter, 6b radio...
Bell System Drawings
Aug 29, 2017 American Telephone & Telegraph Co.
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PANEL SYSTEMS SUBSCRIBER SENDER CIRCUIT 3-1 3-2, OR 2 DIGIT NON COIN ARRANGED WHEN REQUIRED FOR FOUR CLASSES OF SERVICE  FOR USE WITH SENDER SELECTORS AND DECODER CIRCUITS  From the Connections Museum, Seattle WA.
Topics: bell system, circuit description, panel switch, subscriber's senders
Bell System Books
Aug 29, 2017 American Telephone & Telegraph Co.
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Bulletin No. 17 (Preliminary) December 1920 American Telephone and Telegraph Company Department of Development and Research Maintenance Instructions Panel Type Machine Switching System Douglas and Tyler Offices, Omaha
Topics: panel system, bell system, at&t, first panel office, electromechanical switching
Bell System Books
Aug 29, 2017 American Telephone & Telegraph Co.
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This volume is part of a school course on the No. 1 Crossbar Dial System. It is a companion to the book of diagrams, which can be found here . The copy I scanned is missing one photo, as the original page is gone. I may find another copy with that photo, and re-upload at some point.  From the archive at the Connections Museum, Seattle WA.
Topics: bell system, telephony, western electric, AT&T, crossbar, crossbar switching, 1xb, no. 1...
Bell System Books
Jul 26, 2017 Operation and Engineering Department
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Bell System training document with sequence charts and operational sketches of Panel Dial System circuits. This volume covers only the BCO (Battery Cut-Off) variant of the Panel system.
Topics: panel switch, bell system, telephony, switching
Bell System Books
Jul 26, 2017 Operation and Engineering Department
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Bell System training document with sequence charts and operational sketches of Panel Dial System circuits. This volume covers only the GCO (Ground Cut-Off) variant of the Panel system.
Topics: panel switch, bell system, telephony, switching
Bell System Books
Jul 25, 2017 Illinois Bell Telephone Co.
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The Bell Telephone News Volume Nine April, 1920
Topics: bell system, at&t, magazine, telephone, periodicals, 1920s
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Bell System Books
Jul 22, 2017 New York Telephone Company
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Long Island Guide Avalon Office File Plant Training Practices Crossbar System Prepared by Long Island Division New York Telephone Company Copyright 1939 by American Telephone & Telegraph Company Printed in U.S.A.
Topics: bell system, at&t, switching, crossbar, 1xb, telephone switching
Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 18, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 17, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 17, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 17, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 17, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 17, 2017 American Telephone & Telegraph Company
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Bell System Practices
Jul 17, 2017 American Telephone & Telegraph Company
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Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T
Bell System Drawings
Jul 10, 2017 Western Electric Co.
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Topics: panel switch, circuit description, bell system, telephone switching, AT&T