Bell System X-Specifications

Section Date Issue Size Title
X-212521998-04-171.1321.09 KBShipping Container Direct Marking Requirements
X-639401960-04-01114.01 MBThe Electronic Switching System - Trial Installation, Morris, Illinois - General Description
X-647001950-03-0113.08 MBEquipment Nomenclature
X-65518-011932-04-01142.01 MBTools and Gauges for Maintenance Purposes in Local Manual Central Offices and Manual P.B.X.'s
X-70035-011927-03-071328.12 KBInstallation and Maintenance Requirements for No. 1 Type Electric Clocks
X-70059-011928-03-221D90.69 KBRequirements and Adjusting Procedures for Central Office and PBX Apparatus - 87 Type Relays
X-70076-011928-09-102D223.65 KBRequirements and Adjusting Procedures for Central Office and PBX Apparatus - 208 and 214 Type Relays
X-70077-011928-12-042D397.79 KBRequirements and Adjusting Procedures for Central Office and PBX Apparatus - "A" and "AB" Type Relays
X-70085-011927-05-131462.52 KBInstallation and Maintenance Requirements for No. 50-A Dial Testers
X-70097-011927-12-031252.46 KBInstallation and Maintenance Requirements for 186 Type Relays
X-70218-011926-05-051282.92 KBInstallation and Maintenance Requirements for No. 5 Type Traffic Registers
X-70263-011928-05-152B1000.98 KBRequirements and Adjusting Procedures for Central Office and PBX Apparatus - Panel District, Office, Incoming and Final Selector Elevator Apparatus (No. 11 Type and D-85387 Multiple Brushes, No. 2 and No. 9 Type Brush Rods, No. 1 Type Trip Rods, No. 8 Type Indicators and No. 1-A Guides)
X-70291-011926-05-271290.03 KBInstallation and Maintenance Requirements for The Foote-Pierson & Co. Ink Writing Register (Single Pen Register) per KS-3106
X-70302-011927-04-301373.21 KBInstallation and Maintenance Requirements for Panel Link District Finder and Sender Selector Elevator Apparatus (No. 12 Type Multiple Brushes, No. 9 Type Brush Rods, No. 2 Type Compensators and No. 1-A Guides)
X-70303-011928-09-282D168.85 KBRequirements and Adjusting Procedures for Central Office and PBX Apparatus - 10 and 11 Type Bells and 10 Type Buzzers
X-70311-011928-04-051D129.56 KBRequirements and Adjusting Procedures for Central Office and PBX Apparatus - Cleaning Procedures for Key Contacts
X-720041924-06-201301.37 KBInstallation and Maintenance Requirements for AC Unit Drive Motors - Panel Machine Switching Systems
X-72026-011928-04-262569.76 KBInstallation and Maintenance Requirements for "M" Type Charging Generators per KS-5009
X-755091967-11-0148.49 MBEngineering Reference Data - Wire Spring Relays - AF-, AG-, AJ-, AK-, AL-, & AM-Types
X-755121964-11-015.93 MBEngineering Reference Data - Bell System Transmission Transformers