Bell System Practices

A typical volume of Bell System Practices from the 1970s.

The Bell System Practices (BSPs) is a compilation of technical publications which describes the best methods of engineering, constructing, installing, and maintaining the telephone plant of the Bell System under direction of AT&T and Bell Telephone Laboratories.[1] Covering everything from accounting and human resources procedures through complete technical descriptions of every product serviced by the Bell System, it includes a level of detail specific to the best way to wrap a wire around a screw, for example.

With sections regularly updated, printed and distributed, the BSPs were the key to the standardized service quality throughout the Bell System. They enabled employees, who had never met previously, to easily work with one another in the event of a service outage, a disaster, or merely when relocating. Updates cover manufacturing changes phased into production during a product's lifetime of interest to the installer, including changed product features, internal component parts, available colors and installation procedures. Collectors also use these documents to help date and restore vintage telephones.

Document organization

Issuance of Bell System Practices within the Bell System started in the late 1920s, when they replaced a similar compendium, the AT&T Handbook Specifications. Initially, BSPs were identified by mixed alphanumeric sequence numbers designating a section and a specific document number within each section. The sections consisted of one letter and two digits, followed by a period character and a three-digit document number. The version of each document was indicated by an issue number. For example, the section designation C34.175 Issue 1 identified a document entitled Station Dials—2 and 4 Types—Maintenance.

In the 1950s, the format of BSP designations was changed to a nine-digit numerical format, written in three groups of three digits. The first three digits referred to the division, which indicated a broad subject area, such as subscriber sets or the No. 1 ESS. The next three digits indicated a specific subject area, such as the specific type of equipment used within the major division subject. The final three digits indicate the serial number of the document. The content could be general descriptive information, information on wiring and connections, test procedures, or piece-part replacement and repair information.

The BSP documents were produced in primarily two formats, 8 1/2"x11" pages for use in office environments, and in a small, portable format (4" x 6 7/8") for use by installers on the job, carried in their service trucks. Starting in the 1970s the most frequently used BSPs were bundled in convenient handbooks each covering general subject matters, such as the Station Service Manual.

The 9-digit format and numbering system was also used by Nortel and ITT Corporation due to their provenance from the Bell System's manufacturing unit, Western Electric.

Changes after divestiture

After the Bell System divestiture of 1984, AT&T maintained the basic organization and maintenance of the publication under the revised name AT&T Practices, but the publication was later divided among the new companies created by divestiture. Specifically, the AT&T Practices covered most equipment topics that stayed with Bell Labs, which acquired the name AT&T. Bellcore Recommendation covered network maintenance and design topics transferred to Bellcore. Bell Service Practices (and variations) referred to the plant and technical reference maintained by the various Regional Bell Operating Companies. Lucent Technology Practices, and other publications contained product lines taken over by the respective manufacturers. Avaya and Alcatel-Lucent still publish practices using the 9-digit section numbering format.

BSP nine-digit numerical index

Section Reference Description
GENERAL INFORMATION 000-000-000 General Information - Bell System Practices
GENERAL INFORMATION 000-000-001 Master Alphabetical Index - All Divisions
GENERAL INFORMATION 000-000-005 Master Numerical Index - All Divisions
GENERAL INFORMATION 000-000-006 Index of Maintenance Practices Available in Handbook Size
GENERAL INFORMATION 000-000-007 Master Alphabetical Index—Task Oriented Practices
GENERAL INFORMATION 001-000-000 (Reserved for company-issued administrative practices. The Number assignments are to be made locally.)
GENERAL INFORMATION 002-000-000 (Reserved for company-issued administrative practices. The Number assignments are to be made locally.)
GENERAL INFORMATION 003-000-000 (Reserved for company-issued administrative practices. The Number assignments are to be made locally.)
GENERAL INFORMATION 004-000-000 (Reserved for company-issued administrative practices. The Number assignments are to be made locally.)
GENERAL INFORMATION 005-000-000 Abbreviations, Definitions, Drawings, Requirement Tables, Specifications, and Symbols
GENERAL INFORMATION 006-000-000 Microfilm Systems
GENERAL INFORMATION 007-000-000 Information Systems
GENERAL INFORMATION 010-000-000 General Methods
COMMON 020-000-000 General Information- Divisions 020 to 178 Inclusive
APPARATUS 024-000-000 Amplifiers, Controllers, Control Units, Regulators, and Electron Tubes
APPARATUS 026-000-000 Banks, Clutches, Commutators and Commutator Brushes, Elevator Apparatus, Multiple Brushes and Rods, and Trip Rods for Panel Offices - Circuit Breakers, Compensators, Connectors, Control Panels, Fuses and Mountings, Magnetic Switches, Selectors, and Starters
APPARATUS 028-000-000 Autotransformers, Bells, Buzzers, Dials, Dial Adapters and Mountings, Gongs, Head Telephone Sets, Headsets, Potentiometers, Rheostats, Ringers, and Sounders
APPARATUS 030-000-000 Calculogrophs, Call Timing Switch, Cameras, Clocks, Counters, Photo Processors, Registers, Selector Multiple Designation Cards, Switches, Tape Printers, Ticketers, Timers, and Time Stamp
APPARATUS 032-000-000 Capacitors, Connectors, Cords, Cord Reels, Diodes, Drops, Jacks, Keys, lamps, Plugs, Resistors, Signals, Sockets, Thermistors, Transistors, and Varistors
APPARATUS 034-000-000 Distributors, Regenerators, and Regenerative Repeaters for Teletypewriter Service - AMA Tope Reels and Reeler, Cleaning Cabinet, Perforators, Readers, Recorders, Recorder Reproducers, Tape Announcing Machine, and Translators
APPARATUS 040-000-000 Relays
MISCELLANEOUS EQUIPMENT, MATERIALS, CIRCUITS, AND METHODS 065-000-000 Miscellaneous Equipment and Materials
MISCELLANEOUS EQUIPMENT, MATERIALS, CIRCUITS, AND METHODS 067-000-000 Concentrators
MISCELLANEOUS EQUIPMENT, MATERIALS, CIRCUITS, AND METHODS 069-000-000 Miscellaneous Methods
TOOLS AND GAUGES 074-000-000 Catalogue Information- Tools
TOOLS AND GAUGES 074-000-000 Index of Tools - Switching System and Power
TOOLS AND GAUGES 075-000-000 Tools and Materials (Common Usage)- Maintenance, Selection, and Use
TOOLS AND GAUGES 076-000-000 Tools and Materials - Switching Systems and Power - Maintenance, Selection, and Use
TOOLS AND GAUGES 080-000-000 Tools and Materials- Customer Equipment
TOOLS AND GAUGES 081-000-000 Tools and Materials - Outside Plant
TOOLS AND GAUGES 084-000-000 Catalogue Information - Gauges - Electrical Indicating Instruments and Meters
TOOLS AND GAUGES 084-000-000 Alphabetical Index - Gauges - Description
TOOLS AND GAUGES 085-000-000 Gouges !Common Usage! - Maintenance, Selection, and Use
TEST EQUIPMENT 100-000-000 Test Equipment, Electrical Indicating Instruments and Meters (Common Usage) - Maintenance, Selection, and Use
TEST EQUIPMENT 102-000-000 Test Equipment, Electrical Indicating Instruments and Meters !Switching Systems and Pawed - Maintenance, Selection, and Use
TEST EQUIPMENT 103-000-000 Transmission Test Equipment
TEST EQUIPMENT 104-000-000 Radio Test Equipment
TEST EQUIPMENT 105-000-000 PBX and Station Test Equipment
TEST EQUIPMENT 106-000-000 Outside Plant Electrical Test Equipment
TEST EQUIPMENT 107-000-000 Data and Teletypewriter Test Equipment
POWER 155-000-000 Alternators, Engine-Alternators, Gas Turbine Alternators, Tone Alternators, Tone Machines, Ringing and Coin Control Generators, Charging Generators and Motor-Generators
POWER 157-000-000 Batteries
POWER 159-000-000 Engines and Engine Sets, Motors, Dynamotors, and Drives
POWER 161-000-000 Speed Reduction Units, Converters, Inverters, Air Dryers, Compressors, Compressor Dehydrators, Dehydrators, Exhauster Sets, Fans, Tube Cooling Systems, Ventilating Equipment, Call Announcer Machines, and Waveguides
POWER 163-000-000 Interrupters, Ringing Machines, and Pole Changers
POWER 167-000-000 Power Plants, Power Units, and Power Supply
POWER 169-000-000 Rectifiers and Filament Supplies
POWER 171-000-000 Miscellaneous Power Circuits and Equipment
SIGNALING EQUIPMENT 179-000-000 Signaling Circuits and Associated Ringer Circuits
OPERATIONS SUPPORT SYSTEMS 190-000-000 Operations Centers and Support Systems - Operations, Maintenance, and Administration
SWITCHING SYSTEMS 201-000-000 Supplemental Information - Central Offices
SWITCHING SYSTEMS 201-000-005 Alphabetical Index for Division 201
SWITCHING SYSTEMS 205-000-000 Automatic Data Test Circuits
SWITCHING SYSTEMS 210-000-000 Service Observing, and Plant and Traffic Desks
SWITCHING SYSTEMS 211-000-000 No. 1, 3, 5, and 6 Toll Offices; No. 1, 3, 5, and 6 Toil Switchboards; and No. 6A Teletypewriter Switchboard
SWITCHING SYSTEMS 212-000-000 No. 4A and 4M Toil Switching Systems
SWITCHING SYSTEMS 215-000-000 Panel Offices
SWITCHING SYSTEMS 216-000-000 No. 1 Crossbar Offices
SWITCHING SYSTEMS 218-000-000 No. 3, No. 5, and No. 5A Crossbar Offices
SWITCHING SYSTEMS 218-000-001 Alphabetical index.- No. 5 Crossbar
SWITCHING SYSTEMS 218-000-002 Alphabetical Index - No. 5A Crossbar
SWITCHING SYSTEMS 218-000-003 Alphabetical Index - No. 3 Crossbar
SWITCHING SYSTEMS 218-779-000 Alphabetical Index - No. 5 Crossbar Offices - Arranged With Call Data Transmitter
SWITCHING SYSTEMS 218-799-000 Alphabetical Index - No. 5 Crossbar Offices - Arranged With Electronic Translation System
SWITCHING SYSTEMS 220-000-000 Crossbar Tandem Offices
SWITCHING SYSTEMS 225-000-000 Testing Information Applying to Specific Step-byStep and Community Dial Offices
SWITCHING SYSTEMS 226-000-000 Equipment Common to More Than One Type Step-by-Step and Community Dial Office
SWITCHING SYSTEMS 226-000-005 Alphabetical Index - Step-by-Step and Community Dial Offices
SWITCHING SYSTEMS 227-000-000 General and Testing Information Applying to Intertoll Dialing, CAMA, AMA, ANI, "TOUCH-TONE®" Calling and Common Control Equipment - Step-by-Step Systems
SWITCHING SYSTEMS 230-000-000 Data Network Systems
SWITCHING SYSTEMS 230-100-006 Transaction Network - Reference and Supplemental Information
SWITCHING SYSTEMS 231-000-000 No. 1 and No. 1A Electronic Switching Systems (ESS)
SWITCHING SYSTEMS 231-000-001 Alphabetical Index of 231 Division Section Titles—No. 1 and. No. 1A Electronic Switching Systems
SWITCHING SYSTEMS 232-000-000 No. 2 Electronic Switching System (ESS)
SWITCHING SYSTEMS 233-000-000 No. 3 Electronic Switching System (ESS)
SWITCHING SYSTEMS 233-000-010 Interdivisional Numerical Index - Excluding Division 233 - No. 3 Electronic Switching System
SWITCHING SYSTEMS 234-000-000 No. 4 Electronic Switching System (ESS)
SWITCHING SYSTEMS 234-000-005 Interdivisional Numerical Index - No. 4 Electronic Switching System
SWITCHING SYSTEMS 235-000-000 No. 5 Electronic Switching. System (ESS)
SWITCHING SYSTEMS 240-000-000 No. 1 0 1 Electronic Switching System (ESS)
SWITCHING SYSTEMS 241-000-000 General Trade Switching Systems
SWITCHING SYSTEMS 250-000-000 Traffic Service Systems
SWITCHING SYSTEMS 252-000-000 Traffic Management Systems
SWITCHING SYSTEMS 254-000-000 Stored Program Control
SWITCHING SYSTEMS 255-000-000 Processor Controlled Ancillary Systems
SWITCHING SYSTEMS 250-000-010 Interdivisional Numerical Index - No. 1 A Voice Storage System
SWITCHING SYSTEMS 256-000-000 Common Channel Signaling System (CCSS)
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 300-000-000 Transmission Systems and Testing - Cross Reference lists
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 301-000-000 Transmission Performance Measurement Plans
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 302-000-000 Transmission Test Line Directories
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 304-000-000 Transmission Data
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 309-000-000 Switched Services Networks
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 310-000-000 Nonswitched Special Services System
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 311-000-000 Switched Special Services Systems
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 312-000-000 Private Line Data Systems and Services
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 314-000-000 Digital and Analogue Data Transmission Systems
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 318-000-000 Television Systems
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 320-000-000 Program Transmission Systems and Services
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 330-000-000 Cable and Open-Wire Testing and Trouble location Methods
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 331-000-000 Transmission Noise Testing, Central Office PBX Customer lines and Equipment
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 332-000-000 Voice-frequency Telephone Repeaters, Pilot Wire Regulators, Echo Suppressors, Composite Sets and Associated Equipment
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 333-000-000 Interoffice Signaling Systems and Testing
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 340-000-000 PICTUREPHONE® Services - Baseband Video Transmission
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 341-000-000 PICTUREPHONE® Transmission - Performance Plan
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 354-000-000 Frequency Generating Systems
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 355-000-000 Type K Carrier Telephone Systems and Associated Equipment Components
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 356-000-000 Analog Multiplex Terminal Equipment
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 357-000-000 Wire-Line Entrance Links and Broadband Entrance Links and Interconnection
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 358-000-000 Type L1 Carrier Telephone System and Associated Equipment Components
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 359-000-000 L3, L4, L4S, L5, and LSE Carrier
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 360-000-000 Maintenance Center Tests - Equipment Components- Type L1 and L3 Carrier Telephone Systems
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 361-000-000 Service Center Tests - type N, 0, and ON Carrier Systems
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 362-000-000 Type N, 0, and ON Carrier Telephone Systems and Associated Equipment Components
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 363-000-000 Pair Gain Systems
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 364-000-000 Submarine Cable Systems !long lines Only!
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 365-000-000 Digital Transmission Systems
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 370-000-000 TA SI (long Lines Only)
TRANSMISSION AND SIGNALING SYSTEMS AND TESTING 371-000-000 Broadband Restoration
RADIO 400-000-000 Radio Administration
RADIO 402-000-000 Antennas, Transmission lines, and Waveguide
RADIO 403-000-000 Coastal Harbor, High Seas, Overseas, and Emergency Point-to-Point Radio
RADIO 404-000-000 Manual Mobile Radio
RADIO 405-000-000 NJ, MKS, and ML Mobile Radiotelephone
RADIO 406-000-000 Air-Ground Radio
RADIO 407-000-000 Personal Radio Services
RADIO 408-000-000 Motorola, RCA, Federal, REL, Narrow band Auxiliary Channel and Other Non-Western Electric Microwave Radio, and TV Off-the-Air Pick-Up Services
RADIO 409-000-000 TE, DT, Tl, and TM Microwave Radio
RADIO 410-000-000 TD-2 Microwave Radio
RADIO 411-000-000 TD-3 Microwave Radio
RADIO 412-000-000 TH-1 Microwave Radio
RADIO 413-000-000 TH-3 Microwave Radio
RADIO 415-000-000 TD-3 Microwave Radio
RADIO 416-000-000 TN-1 Microwave Radio
RADIO 417-000-000 3A-Radio Digital Systems
RADIO 419-000-000 Single Sideband Microwave Radio Systems
RADIO 420-000-000 Microwave Radio - Common Equipment
RADIO 421-000-000 FR/DR Microwave Radio System
RADIO 422-000-000 Common Microwave Radio- Transmission Systems
CUSTOMER EQUIPMENT 460-000-000 General Information
CUSTOMER EQUIPMENT 460-000-006 Alphabetic-Numeric Index - Station, Key, PBX, and Private Service Systems
CUSTOMER EQUIPMENT 461-000-000 Wiring and Cabling
CUSTOMER EQUIPMENT 462-000-000 Drop and Block Wiring and Dedicated Plant
CUSTOMER EQUIPMENT 463-000-000 Miscellaneous Station Apparatus for Use With Station Installations
SPECIAL SERVICES 471-000-000 Other Common Carriers
SPECIAL SERVICES 473-000-000 Intro-PBX Protection of Service, Code Calling, Customer Training, Dispatching, Emergency Reporting, Interface Trunks, Message Waiting, Recorded Telephone Dictation, Telephone Answering Systems, and Transmitter Transfer
SPECIAL SERVICES 475-000-000 Call Distributing System No. IS, Information Desks, and Order Turrets
SPECIAL SERVICES 476-000-000 Force Administration Data System (FADS)- Automatic Call Distributing System (ACD), No. 2A, 28, and 3A and Call Distributing System No. 4A
SPECIAL SERVICES 480-000-000 Private Service Systems
SPECIAL SERVICES 481-000-000 Teleconferencing Service
STATION EQUIPMENT 500-000-000 General Considerations for Station Installations
STATION EQUIPMENT 501-000-000 Station Set Components
STATION EQUIPMENT 502-000-000 Common Battery Station Sets
STATION EQUIPMENT 503-000-000 Modular Station Sets - Common Battery
STATION EQUIPMENT 504-000-000 Selector Consoles, Telephone Consoles, and Apparatus Units
STATION EQUIPMENT 506-000-000 Public telephone Sets
STATION EQUIPMENT 508-000-000 Public Telephone Enclosures and Miscellaneous Accessories
STATION EQUIPMENT 510-000-000 Station Sets and Coin Collectors—local Battery and Magneto
STATION EQUIPMENT 512-000-000 Automatic Dialers, Station Keys, Key Equipment, Interphone Systems, Modular Units, and Speakerphone Systems
STATION EQUIPMENT 514-000-000 Telephone Answering and Announcement Sets and Systems
STATION EQUIPMENT 518-000-000 Key Telephone Systems, Video Telephone Stations, and Switching Systems
STATION EQUIPMENT 518-451-110 HORIZON® Communications System - Feature Document Cross-Reference Guide
STATION EQUIPMENT 529-000-000 Station Apparatus and Equipment Intended Solely for Specially-..engineered lines - Not for General Telephone Use
PRIVATE BRANCH EXCHANGES 533-000-000 Customer Premises Systems (ESS Provided Customer Services)
PRIVATE BRANCH EXCHANGES 533-000-001 Interdivisional Alphanumeric Indexes - ESS Provided Services -Customer Premises Systems
PRIVATE BRANCH EXCHANGES 534-000-000 Sections Applying to More Than One PBX Series - 500, 600, 700, and 800 Series- Manual and Dial PBX
PRIVATE BRANCH EXCHANGES 536-000-000 500 Series PBX
PRIVATE BRANCH EXCHANGES 538-000-000 600 Series PBX
PRIVATE BRANCH EXCHANGES 540-000-000 Sections Applying to More Than One 700 Series PBX Including Centrex CU, Attendant Equipment for Centrex CO, and "TOUCH-TONE®" Calling
PRIVATE BRANCH EXCHANGES 541-000-000 700C and 710C PBX
PRIVATE BRANCH EXCHANGES 542-000-000 701- and 711-Type PBX
PRIVATE BRANCH EXCHANGES 543-000-000 702A PBX
PRIVATE BRANCH EXCHANGES 546-000-000 740-Type PBX
PRIVATE BRANCH EXCHANGES 548-000-000 750A PBX
PRIVATE BRANCH EXCHANGES 550-000-000 755A PBX
PRIVATE BRANCH EXCHANGES 551-000-000 756A, 757A, 758A, 758B, 758C, 761, and 770 PBX
PRIVATE BRANCH EXCHANGES 553-000-000 800 Series PBX
PRIVATE BRANCH EXCHANGES 554-000-000 "DIMENSION®" PBX
PRIVATE BRANCH EXCHANGES 554-191-100 "DIMENSION®" PBX- Feature Document Reference Guide
TELETYPEWRITER AND OTHER DATA TERMINALS 570-000-000 Teletypewriter General Information - Miscellaneous Apparatus and Auxiliary' Equipment
TELETYPEWRITER AND OTHER DATA TERMINALS 570-000-003 Master Cross-Reference Index of Port Numbers and Associated 9-digit Sections
TELETYPEWRITER AND OTHER DATA TERMINALS 572-000-000 14- 15-, 19-, and 20-Type Teletypewriters
TELETYPEWRITER AND OTHER DATA TERMINALS 573-000-000 28- Type Teletypewriters
TELETYPEWRITER AND OTHER DATA TERMINALS 574-000-000 Teletypewriter 30 Series and Teleprinters
TELETYPEWRITER AND OTHER DATA TERMINALS 578-000-000 Miscellaneous Data Terminals
TELETYPEWRITER AND OTHER DATA TERMINALS 579-000-000 Teletypewriter Field Maintenance Practices/Field Installation Maintenance Practices
TELETYPEWRITER AND OTHER DATA TERMINALS 580-000-000 Teletypewriter Switching Systems
TELETYPEWRITER AND OTHER DATA TERMINALS 581-000-000 Teletypewriter Selective Calling Systems
TELETYPEWRITER AND OTHER DATA TERMINALS 582-000-000 DATASPEED® Services- Systems, Services and Components
DATA SYSTEMS 590-000-000 General Information
DATA SYSTEMS 591-000-000 1 00 Series Data Sets and Associated Services
DATA SYSTEMS 592-000-000 200 Series Data Sets and Associated Services
DATA SYSTEMS 593-000-000 300 Series Data Sets and Associated Services
DATA SYSTEMS 594-000-000 400 Series Data Sets and Associated Services
DATA SYSTEMS 595-000-000 500-Type Service Units and Sets for Digital Systems/Services
DATA SYSTEMS 596-000-000 600 Series Data Sets and Associated Services
DATA SYSTEMS 598-000-000 800 Series Auxiliary Equipments
OUTSIDE PLANT 620-000-000 General
OUTSIDE PLANT 620-000-005 Outside Plant - Construction and Maintenance - Permuted Alphabetical Index
OUTSIDE PLANT 621-000-000 Pole Lines
OUTSIDE PLANT 622-000-000 Conduit, Manholes, and Cable Ducts
OUTSIDE PLANT 623-000-000 Open Wire
OUTSIDE PLANT 624-000-000 Multiple Wire
OUTSIDE PLANT 626-000-000 Cables, Wire, and Apparatus - General
OUTSIDE PLANT 627-000-000 Aerial, Block, and House Cable
OUTSIDE PLANT 628-000-000 Underground Cable
OUTSIDE PLANT 629-000-000 Buried Plant
OUTSIDE PLANT 630-000-000 Submarine Cable
OUTSIDE PLANT 631-000-000 Cable Terminals
OUTSIDE PLANT 632-000-000 Cable Splicing
OUTSIDE PLANT 633-000-000 Splice Closures
OUTSIDE PLANT 634-000-000 Electrical Cable Testing and Identification
OUTSIDE PLANT 635-000-000 Electrolysis - Outside Plant
OUTSIDE PLANT 636-000-000 Main Frame Terminations and Connectors
OUTSIDE PLANT 637-000-000 Cable Pressure Systems
OUTSIDE PLANT 637-600-011 Expanded Cable Pressure Monitoring System (CMPS)
OUTSIDE PLANT 638-000-000 Electrical Protection and Bonding
OUTSIDE PLANT 639-000-000 Concentrators - Outside Plant
OUTSIDE PLANT 640-000-000 Outside Plant - Carrier Apparatus
OUTSIDE PLANT 643-000-000 Coil and Capacitor Cases and Apparatus Cases for Inductors and Filters
OUTSIDE PLANT 644-000-000 Upkeep
OUTSIDE PLANT 649-000-000 Construction Equipment - Outside Plant (also see Divisions 010, 075, 081, 106, and 157)
TEST CENTER OPERATION 660-000-000 Test Center Operation
TEST CENTER OPERATION 660-000-005 Alphabetical Index- Test Center Operation (Divisions 660 Through 669)
TEST CENTER OPERATION 660-168-010 Automated Repair Service Bureau - Documentation Index
TEST CENTER OPERATION 662-000-000 Cable and Local Test Desks and Local Test Cabinets
TEST CENTER OPERATION 664-000-000 Test boards for Other Than Special Services
TEST CENTER OPERATION 666-000-000 Testboords and Test Positions for Special Services
TEST CENTER OPERATION 667-000-000 Switched Maintenance Access Systems (SMAS)
TEST CENTER OPERATION 668-000-000 Data Test Centers
LOOP ASSIGNMENT 680-000-000 Loop Assignment - Distribution Service
LOOP ASSIGNMENT 680-000-005 Alphabetical Index - Plant Assignment - Divisions 680 through 689
LOOP ASSIGNMENT 680-400-010 Index - Telephone Set field Inventory Control
LOOP ASSIGNMENT 682-000-000 Trunk Plant and Special Services
MOTOR VEHICLES 720-000-000 Motor Vehicles and Construction Apparatus
MATERIALS MANAGEMENT 740-000-000 General Information
MATERIALS MANAGEMENT 740-000-001 Overall Supplies - Divisions · 740 through 749
MATERIALS MANAGEMENT 740-000-002 Materials Management Operations Safety Procedure References
MATERIALS MANAGEMENT 741-000-000 Supporting Functions
MATERIALS MANAGEMENT 742-000-000 Supply Controls
MATERIALS MANAGEMENT 743-000-000 Supply Ordering and Computer Controls
MATERIALS MANAGEMENT 744-000-000 Supply Distribution
MATERIALS MANAGEMENT 745-000-000 Material Returns
MATERIALS MANAGEMENT 746-000-000 Supply Functions - Miscellaneous
MATERIALS MANAGEMENT 747-000-000 Plug-In Equipment- Central Office and Customer Premises Switching
BUSINESS INFORMATION SYSTEMS 750-000-000 BISP General
BUSINESS INFORMATION SYSTEMS 751-000-000 Common language
BUSINESS INFORMATION SYSTEMS 756-000-000 Trunks and Special Services
BUILDINGS 760-000-000 Building Engineering
BUILDINGS 760-000-005 Alphabetical Index- Divisions 760 and 770- Building Engineering and Building Operation
BUILDINGS 770-000-000 Building Operation
ENGINEERING PLANNING 780-000-000 Network Operations Methods
ENGINEERING PLANNING 780-000-010 Interdivisional Numerical Index - Network Administration Technical Planning
ENGINEERING PLANNING 788-000-000 Business Services Planning and Operations
ENGINEERING PLANNING 788-100-000 Cross-Reference Index- Business Services Facilities Engineering Practices (BSFEP) to Bell System Practices
ENGINEERING PLANNING 788-100-101 Recommended Document list - Business Service Traffic Engineering
ENGINEERING PLANNING 788-102-100 Cross-Reference Index- Business Services Facilities Administrative Practices (BSFAP) to Bell System Practices
ENGINEERING PLANNING 788-102-101 Recommended Document List - Business Services Traffic Administration
ENGINEERING ADMINISTRATION 790-000-000 Engineering Administrative Practices
COMMON LANGUAGE 795-000-000 Common language
COMMON LANGUAGE 795-200-006 Alphabetical Index of Basic, Codes—Common language Equipment Identification (CLE)
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 800-000-000 Cross-Reference lists, Administrative Information, General Equipment Requirements for Installation and Manufacturing, and General Performance Requirements
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 801-000-000 Common Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 802-000-000 Power Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 804-000-000 Toil Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 806-000-000 Radio Systems and Television Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 807-000-000 Data Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 809-000-000 Private Branch Exchange Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 811-000-000 Private Service Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 812-000-000 Station Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 814-000-000 Step-by-Step Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 815-000-000 Panel Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 816-000-000 No, I Crossbar System
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 817-000-000 Tandem Crossbar System
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 818-000-000 No. 4 Type Toil Switching System
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 819-000-000 No. 3, No. 5, and No. SA Crossbar Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 820-000-000 No. 1, 1A, 2, 2A, 3 and 4 Electronic Switching Systems and No. 1A Processor
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 821-000-000 Traffic Service Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 822-000-000 Traffic Management Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 823-000-000 No. 101 Electronic Switching System
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 824-000-000 Operations Support Systems
EQUIPMENT DESIGN AND GENERAL REQUIREMENTS 825-000-000 Common Channel Signaling System (CCSS)
TRANSMISSION ENGINEERING 851-000-000 Special Services Systems - Engineering Design Information
TRANSMISSION ENGINEERING 852-000-000 Exchange Area and Operator Services Transmission
TRANSMISSION ENGINEERING 853-000-000 Toil Transmission
TRANSMISSION ENGINEERING 855-000-000 Carrier Engineering
TRANSMISSION ENGINEERING 856-000-000 Mechanized Transmission Engineering Tools
TRANSMISSION ENGINEERING 857-000-000 Program and Television Engineering
TRANSMISSION ENGINEERING 859-000-000 Signal Transmission - Engineering Considerations
TRANSMISSION ENGINEERING 860-000-000 PICTUREPHONE® Service Transmission Engineering
TRANSMISSION ENGINEERING 865-000-000 Transmission Maintenance Systems Engineering
TRANSMISSION ENGINEERING 870-000-000 Noise Engineering
TRANSMISSION ENGINEERING 873-000-000 Inductive Coordination
TRANSMISSION ENGINEERING 874-000-000 Supply Systems Data
TRANSMISSION ENGINEERING 876-000-000 Protection Practices
TRANSMISSION ENGINEERING 877-000-000 Corrosion Practices
TRANSMISSION ENGINEERING 880-000-000 Data Communications Engineering
OUTSIDE PLANT ENGINEERING 900-000-000 General Information
OUTSIDE PLANT ENGINEERING 900-000-100 Permuted Index - Outside Plant Engineering
OUTSIDE PLANT ENGINEERING 901-000-000 Facility Planning - Study Methods and Tools
OUTSIDE PLANT ENGINEERING 902-000-000 Facility Planning - Applied Transmission
OUTSIDE PLANT ENGINEERING 915-000-000 Facility Design - Systems
OUTSIDE PLANT ENGINEERING 916-000-000 Facility Design - Feeder Facilities
OUTSIDE PLANT ENGINEERING 917-000-000 Facility Design - Distribution Facilities
OUTSIDE PLANT ENGINEERING 918-000-000 Facility Design - Applied Protection
OUTSIDE PLANT ENGINEERING 919-000-000 Facility Design - Structure
OUTSIDE PLANT ENGINEERING 920-000-000 Facility Design - Trunk Facilities
OUTSIDE PLANT ENGINEERING 928-000-000 Facility Support - Engineering Support Functions
OUTSIDE PLANT ENGINEERING 929-000-000 Outside Plant Facility Support - Plant Operating Support functions
OUTSIDE PLANT ENGINEERING 930-000-000 Facility Support - Maintenance and Upkeep
OUTSIDE PLANT ENGINEERING 935-000-000 Management Organizing
OUTSIDE PLANT ENGINEERING 936-000-000 Management Controlling
OUTSIDE PLANT ENGINEERING 937-000-000 Management Coordinating
RADIO ENGINEERING 940-000-000 Radio Engineering
GENERAL DESCRIPTIVE INFORMATION 951-000-000 Equipment Common to More Than One Type of System
GENERAL DESCRIPTIVE INFORMATION 953-000-000 Switchboard, Desks, and Associated Equipment
GENERAL DESCRIPTIVE INFORMATION 955-000-000 Step-by-Step and Community Dial Offices
GENERAL DESCRIPTIVE INFORMATION 957-000-000 No. 1 Crossbar Offices
GENERAL DESCRIPTIVE INFORMATION 958-000-000 No. 5 Crossbar Offices
GENERAL DESCRIPTIVE INFORMATION 966-000-000 Electronic Switching Systems (ESS)
GENERAL DESCRIPTIVE INFORMATION 970-000-000 Transmission Systems
GENERAL DESCRIPTIVE INFORMATION 972-000-000 Teletypewriter and Data Systems (Information Obsolete)
GENERAL DESCRIPTIVE INFORMATION 975-000-000 Signaling Systems
GENERAL DESCRIPTIVE INFORMATION 981-000-000 Equipment on Customers' Premises Special Services and Private Branch Exchanges!
GENERAL DESCRIPTIVE INFORMATION 982-000-000 Private Service Systems
GENERAL DESCRIPTIVE INFORMATION 984-000-000 Traffic Service and Traffic Management Systems

References

  1. ^ A.B. Covey, The Bell System's Best Sellers, Bell Telephone Magazine, Summer 1952, Pages 87—95 (AT&T)

External links

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