Bell Laboratories Record

Note: This is a work in progress, some issues are missing pages.

Special Thanks to americanradiohistory.com and an anonymous donor.

Section Date Issue Size Title
Vol. 1, No. 11925-09-012.20 MB▪ The Model Shop
▪ The Semi-Remote Control Power Board
▪ Mathematical Research
Vol. 1, No. 21925-10-011.46 MB▪ Electrical Stethoscope
▪ The Spinal Cord of a Nation
▪ Analysing the Motion of Mechanical Devices
▪ The Artificial Line
▪ Who Pays Our Salaries?
▪ Modern Economies Replace Historic Power Plant
▪ When the Alarm Rings
▪ Storage "B" Battery Truck
Vol. 1, No. 31925-11-011.46 MB▪ Our New Building
▪ History of the Telephone Pioneers of America
▪ Sound Recording and Reproducing
▪ Six Thousand Lettres a Day
▪ Keeping Time at West Street
▪ The New York-Azores Cable
▪ Telephone Dictation
Vol. 1, No. 41925-12-011.63 MB▪ Our Historical Museum
▪ Multiplex Transmission by Carrier Currents
▪ Carrier-Current Telephone Systems
▪ For Better Radio Reception (548 Type Loud Speaker)
▪ Pressure Testing of Submarine Cables
▪ A Library of Heart Throbs
Vol. 1, No. 51926-01-011.26 MB▪ Carrier-Current Telegraphy
▪ Electro-Mechanical Sound Recording
▪ Mechanical Developments at Hawthorne
▪ Early Developments in Telephone Signalling
Vol. 1, No. 61926-02-012.14 MB▪ Transmission Limits of Telephone Lines
▪ Installing Radio Broadcast Equipment
▪ The First Woman Telephone Operator
▪ The Microscope as an Industrial Tool
▪ Telephone Signalling
▪ Water Cooling in Radio Broadcasting
▪ Stranded Conductor for High Frequency
▪ Apparatus Which Makes Air a Liquid
▪ Assembly Methods for Loading Coil Cases
Vol. 2, No. 11926-03-011.38 MB▪ Clear as Crystal
▪ Developments and Savings in Contact Materials
▪ The General Staff Department
▪ Why the Time-Clock Knobs Are Black
Vol. 2, No. 21926-04-011.80 MB▪ The Aurora
▪ Two-Way Transatlantic Radio Telephony
▪ Textiles for Insulation in Telephone Equipment
▪ Some Uses of the Cathod-Ray Oscillograph
▪ A One-Kilowatt Radio Transmitter for Broadcasting
▪ Development of Communication Systems
▪ The Systems Development Department
▪ How the Laboratories are Heated
▪ The Telephone and the Switching Locomotive
Vol. 2, No. 31926-05-011.99 MB▪ Power Equipment for Safeguarding Telephone Service
▪ Auditory Masking
▪ A Universal Laboratory Transmission-Measuring Set
▪ New Telegraph Equipment
▪ Lubrication and Wear
▪ The Development of Apparatus
▪ Printing Telegraph Connections With Hawthorne
▪ Cable Development Outpost at Hawthorne
Vol. 2, No. 41926-06-011.92 MB▪ The Manufacture of Vacuum Tubes
▪ Selecting an Audio-Frequency Amplifier
▪ The 6025-B Amplifier
▪ Methods of Measuring Children's Hearing
▪ Remote Control of Power Station
▪ New Portable Sets Measure Radio Transmission
Vol. 2, No. 51926-07-011.55 MB▪ Photoelectric Cells
▪ Making the Best Use of Experience
▪ New Cords and Cord Tips
▪ The Vitaphone
▪ An Audible Motion Picture
▪ Transforming Our Power Supply
▪ A Simplified Announcing System
▪ Speech Sounds
Vol. 2, No. 61926-08-011.56 MB▪ Cosmic Rays
▪ Planning a Radio-Telephone System
▪ In Tune or Out of Tune
▪ New Amplifier for Public Address Systems
▪ The First Underground Telephone
Vol. 3, No. 11926-09-011.34 MB▪ Four Years' Progress in Radio Broadcasting
▪ Telegraphy by Typewriter
▪ Odd Tools for Machine-Switching Apparatus
▪ Concealing the Wires
▪ The Ionization Manometer
Vol. 3, No. 21926-10-011.38 MB▪ The Evolution of the Input Transformer
▪ The Silent Drama of Telephony
▪ Our New Radio Laboratory at Whippany
▪ Public-Address Systems
Vol. 3, No. 31926-11-011.21 MB▪ Reducing the Cost of Electrons
▪ Mechanical Distribution of Toll Tickets
▪ A Mechanical Brain
▪ Saving by Swaging
▪ How the P.B.X. Gets Its Power
▪ A Modern Inquisition
▪ The Transmitter Life-Test
Vol. 3, No. 41926-12-011.64 MB▪ A Physical Background for Permalloy
▪ Dispatching Trains by Telephone
▪ When the Radio Squeals
▪ A Piano String Model of the Human Ear
▪ After Office Hours
▪ The Vitaphone Tells Tales of Itself
Vol. 3, No. 51927-01-011.18 MB▪ From Conference to Cable
▪ Accelerated Laboratory Tests
▪ Closing the Books
▪ Gauges for Machine-Switching Equipment
▪ Magnetic Materials
▪ Stroboscopic Analysis
Vol. 3, No. 61927-02-011.54 MB▪ Thermal Agitation of Electricity
▪ The Loudness of Pure Tones
▪ Power Supply for Radio Receivers
▪ Lead Cable Sheath
▪ Measuring to Four Parst in a Billion
▪ Phonograph Records Illustrating Distortion
Vol. 4, No. 11927-03-011.33 MB▪ The String Oscillograph in War and Peace
▪ A New Amplifier for Train Dispatching
▪ A Rectifier for Train Dispatching
▪ The Printed Form
▪ Electro-Mechanical Oscillators
▪ The Printed Form
▪ Electromechanical Oscillators
Vol. 4, No. 21927-04-011.36 MB▪ Are Electrons Waves?
▪ Marking the Overload Point
▪ Mechanical Filters
▪ An Announcing System for Battleships
▪ Cable Corrosion
▪ The Electrolytic Condenser
▪ Frequency Measurements with the Cathode Ray Oscillograph
▪ Measuring the Resistance of Sliding Contacts
Vol. 4, No. 31927-05-011.96 MB▪ The First Demonstration of Television
▪ Television by Radio
▪ Physical Principles and Apparatus
▪ Research and Development Leading to Television
▪ Television -- A Group Achievement
Vol. 4, No. 41927-06-011.76 MB▪ A New Type of Toll Switchboard
▪ Iron Crystals
▪ Long Waves or Short
▪ Light Finish in Central Offices
▪ Development of Light-Colored Finishes
▪ Eavesdropping on Bank Robbers
▪ Novel Devices for Lubrication
▪ Research Design
Vol. 4, No. 51927-07-011.16 MB▪ Insulation for Submarine Cables
▪ The Television Timer
▪ Wax Lubricants
▪ Quality Rating of Telephone Products
▪ Drafting of Telephone Systems
▪ A Direct-Reading Inductance Standard
▪ Flood-Time Telephone Service
▪ Cooling Our Drinking Water
Vol. 4, No. 61927-08-011.31 MB▪ The Hardening of Lead
▪ Measuring Dial Speeds
▪ Eleven Miles of Wire
Vol. 5, No. 11927-09-011.59 MB▪ A New Era in Loading
▪ New Step-by-Step Equipment
▪ The Life History of an Adsorbed Atom
▪ A Tour Through the Microscopic Laboratory
▪ Cutting Expense Corners in Systems Drafting
Vol. 5, No. 21927-10-011.70 MB▪ Hearing Aids and Deafness
▪ The Polarity of Learning
▪ A Compact Direct-Current Amplifier
▪ A Practical Short-Wave Oscillator
▪ Sheet Insulating Materials
Vol. 5, No. 31927-11-013.08 MB▪ Power Rating of Broadcasting Transmitters
▪ The Fifty-Kilowatt Radio Transmitter
▪ Working the Base Metals
▪ Echo Elimination in Transatlantic Service
▪ Polishing the Contacts of Telephone Plugs
▪ Saving the Tracing in the Systems Drafting Group
▪ Telephone Service Opened with Mexico
Vol. 5, No. 41927-12-011.49 MB▪ A Statement of Policy
▪ Fifty Years of Telephone Plugs
▪ Humidity Test Equipment
▪ Commercial Generator for Central Office Power Plants
▪ Cable Splicers' Test Set
▪ Strength-Tests of Telephone Materials
Vol. 5, No. 51928-01-011.42 MB▪ Twenty Years at West Street
▪ The Dufour Cathode-Ray Oscillograph
▪ A Brake for Rolling Ladders
▪ New Rubber Compression Testing Machine
▪ Saving Days and Dollars With Shears
▪ The 5-A Audiometer
▪ High Voltage Storage Battery
Missing pp. 146-147
Vol. 5, No. 61928-02-011016.23 KB▪ Ionized Regions in the Atmosphere
▪ New Specifications for Raw Materials
▪ The Use of Codes in Electrical Communication
▪ Psychology Aids in Tests of Hearing
▪ New Languages from Old
▪ "What Are the Chances That…"
▪ Tooling-Up the Drafting Room
▪ The Twenty-Four Inch Cone
Vol. 6, No. 11928-03-013.06 MB▪ A New Loud-Speaking Receiver
▪ Step-by-Step Cordless "B" Board
▪ New Devices in Television
▪ Radio Installations in South America
▪ Water Cooling for Radio
Vol. 6, No. 21928-04-011.41 MB▪ "Signal Shaping" for Submarine Cables
▪ Platinum Alloys for Vacuum Tube Filaments
▪ Our Insurance Plan
▪ Carrier Telegraph in Canada
▪ The Local Circuit Development Laboratory
▪ Permalloy in Audio Transformers
Vol. 6, No. 31928-05-011.77 MB▪ The Decoder
▪ Differential Equations and Law
▪ Telephone Service Opened with Paris
▪ Phonograph Records of Heart Sounds
▪ Amplification Behind the Talking Movies
▪ Spectrographic Analysis
▪ The Laboratories Take to the Air
▪ Rotary File Type Information Desk
▪ Life Insurance Protection
Vol. 6, No. 41928-06-011.10 MB▪ Systematized Research
▪ New Standards in Emergency Power-Supply Units
▪ Sound-proof Rooms
▪ The Light of a Television Eye
▪ Amplifier for Condenser Transmitter
▪ Terminal Strips
▪ "To Have and To Hold"
Vol. 6, No. 51928-07-011.23 MB▪ Research Methods
▪ A Short-Haul Carrier System
▪ Determining Short-Wave Paths
▪ A New Non-Multiple P.B.X.
▪ Some Early Cable Terminals
▪ Very Thin Films of Rubidium
Vol. 6, No. 61928-08-011.44 MB▪ Some Facts about Frequency Measurement
▪ Continuous Charging for Automatic Branch Exchanges
▪ Acoustic Filters
▪ Apparatus Analysis
▪ Announcing the 740-A P.B.X.
▪ A New Method in Television
▪ The Opening of Transatlantic Service on Short Waves
▪ Taking the Harm Out of Harmonics
▪ An Efficient Driving Coil for Loud Speakers
Vol. 7, No. 11928-09-011.11 MB▪ The Perminvars, a Group of New Magnetic Alloys
▪ Hunting Features in the Panel System
▪ Cable Terminals
▪ The Grid-Current Modulator
▪ Insuring Central-Office Power Supply
▪ Frequency Control for Broadcasting
▪ The Rest Room in New Dress
Vol. 7, No. 21928-10-011.54 MB▪ Airways Communication Service
▪ The Nobel Laureates
▪ Human Errors and the Dial Telephone
▪ Critical Relays of the Telephone System
▪ Lever Type Keys
Vol. 7, No. 31928-11-012.18 MB▪ Reproducing Sound and Scene
▪ Fundamentals of Speech, Hearing and Music
▪ General Principles of Sound Recording
▪ Recent Advances in Wax Recording
▪ Sound Recording with the Light Valve
▪ Speed Control for the Sound-Picture System
▪ Sound Projector Systems for Motion-Picture Theaters
▪ Installation and Adjustment of Western Electric Sound-Projector Systems
Vol. 7, No. 41928-12-012.49 MB▪ "TU" Becomes "Decibel"
▪ Composite Telegraphy
▪ Panel Senders
▪ The Mechanical Delay-Network
▪ Development of the Impedance Bridge
▪ Coil Corrosion
▪ Trunk Hunting Switches
▪ Locating Faults on Toll Lines
Vol. 7, No. 51929-01-011.30 MB▪ Particles and Waves
▪ Transmission Regulating System for Toll Cables
▪ Corrosion of Lead Cable Sheath
▪ High-Strength Aluminum Alloys for Diaphragms
▪ Couteracting Dialing Errors in the Step-by-Step System
▪ Operators' Transmitters and Receivers
Vol. 7, No. 61929-02-012.01 MB▪ An Introduction to "Speech and Hearing"
▪ Development of the 1800-Pair Cable
▪ Private Branch Exchanges
▪ Atomic Physics and Circuit Theory
▪ Development of Step-by-Step Line Finders
▪ New Equipment for Voice-Frequency Telegraphy
▪ Ringing Machines for Small Offices
Vol. 7, No. 71929-03-011.60 MB▪ Leadership in Industrial Research
▪ Curious Patents in Mechanical Switching
▪ A New Telephone Door for the Retail Shop
▪ Saving Lead in Toll Offices
▪ Direct Scanning in Television
▪ Transmission Testing of Central-Office Circuits
▪ Small Power Plants for Telephone Repeaters
▪ Level Hunting Connectors
Vol. 7, No. 81929-04-011.22 MB▪ Textiles as Insulators
▪ Washed Textile Insulation for Central-Office Wiring
▪ Laying a Foundation for Aircraft Communication
▪ A New Radio Receiver for Commercial Airplanes
▪ Straightforward Trunking
▪ The Electromagnetic Oscillograph in the Circuit Laboratory
▪ A New Cordless Switchboard
Vol. 7, No. 91929-05-011.70 MB▪ What's a Good Loud Speaker?
▪ Extending the Usefulness of the Oscillograph in Circuit Testing
▪ Patents as a Means of Both Protection and Publication
▪ The Pulse Corrector
▪ Routine Tests in a Panel Office
▪ Graphical Symbols for Telephone and Telegraph Use
▪ Trouble Indicator
Vol. 7, No. 101929-06-011.46 MB▪ Picture Transmission in England
▪ Toll-Line Signalling
▪ Panel Fundamental Circuit
▪ All-Relay Register Circuit
▪ A Slide Rule for Vector Calculations
▪ Condensers for Many Uses
Vol. 7, No. 111929-07-011.79 MB▪ New Short-Wave Radio Stations
▪ Television in Colors
▪ Rotating the "Wax" for Sound Pictures
▪ A Carrier Telephone System for Power Lines
▪ Capability Engineering of Step-by-Step Relays
Vol. 7, No. 121929-08-012.51 MB▪ The Story of Short-Wave Transoceanic Telephony
▪ Transmitting Station at Lawrenceville, N.J.
▪ The Transatlantic Short-Wave Transmitters
▪ Short-Wave Transmitting Antennas
▪ The Transatlantic Short-Wave Receivers
▪ Short-Wave Receiving Antennas
Vol. 8, No. 11929-09-012.15 MB▪ Transatlantic Telephone Cable
▪ The Master Reference System for Telephone Transmission
▪ Voice-Frequency Equipment for the Transatlantic Radio Telephone
▪ Power Supply for Voice-Frequency Equipment, Transatlantic Short-Wave Radio
▪ The Commercial Problems in Engineering the Transoceanic Short-Wave Radio System
▪ Reproducing Machien for Picture and Sound
▪ Tie Lines Between Private Branch Exchanges
▪ A New Dial PBX of Large Capacity
Vol. 8, No. 21929-10-011.24 MB▪ High-Frequency Quartz-Crystal Oscillators
▪ Short-Wave Vacuum Tubes for Transoceanic Service
▪ Restoring Speech
▪ Bearings in Power-Driven Telephone Apparatus
▪ Methods of Handling Toll Calls
▪ Season-Cracking of Metals
Vol. 8, No. 31929-11-012.00 MB▪ Viscosity in Solids
▪ Permeameters for Measurements over Wide Temperature Ranges
▪ A New Multiple P.B.X.
▪ A Thousand-Ampere Choke Coil
▪ Calling Subscribers to the Telephone
▪ Standard Housings for Portable Test Sets
▪ Adjustment Provisions for Central Office Apparatus
Vol. 8, No. 41929-12-011.96 MB▪ Taking Chances in Inspection-by-Sampling
▪ A New Emergency Power Supply Unit
▪ Lacquering and Plating in the Laboratories
▪ Impedance Bridges
▪ Evolution of the Call-Indicator System
▪ An Outline of Step-by-Step Organization
▪ A Method for Estimating Audible Frequencies
Vol. 8, No. 51930-01-012.63 MB▪ Telephony Between Ship and Shore
▪ The Call Announcer
▪ Systems Drafting Moves
▪ Outside Plant Development New Quarters
▪ A Low-Insulation Alarm for Toll Cables
▪ Notes on Panel Development
▪ The Manual Tandem Board
Vol. 8, No. 61930-02-012.68 MB▪ New Sound-Picture Laboratory
▪ Testing Ringers and Dials at Subscribers' Stations
▪ Idle Trunk and Position Indicating
▪ The Telephone in its Infancy
▪ Economics of Relay Winding Design
▪ A New Dial PBX for Residences
▪ The New Chicago Toll Office
Vol. 8, No. 71930-03-011.99 MB▪ The Prior Art
▪ Prevention of Crosstalk in Phantom Loading Units
▪ Function of the Toll Circuit Laboratory
▪ Telephone Line Insulators
▪ Excellence in Auditoriums
▪ Improved Equipment for Information Service
▪ A New Timing Disc for the Oscillograph
▪ Bell System Contributors to the Encyclopaedia
Vol. 8, No. 81930-04-012.50 MB▪ A Year of Progress in Telephony
▪ Discontinuities in Magnetization
▪ Recording the Sound Picture
▪ Sound-Picture Slang
▪ A New Electrolysis Switch
▪ Clutches for the Panel System
▪ A Thousand-Cycle Frequency Standard
▪ New Equipment for Central Office Supervision
▪ Synthetic Photography
Vol. 8, No. 91930-05-013.31 MB▪ Two-Way Television
▪ Radio Engineering in Buenos Aires
▪ Subscriber's Line Finder and District Selector
▪ A Dial PBX for Large Residences
▪ The New Telephone Booth
▪ Shipping and Transportation
▪ A New Main Distributing Frame for Large Offices
Vol. 8, No. 101930-06-012.04 MB▪ Dials for the Flying Fleet
▪ A Cathode Ray Hysteresigraph
▪ Steel-Tape-Armored Toll Cable
▪ Die Castings
▪ Toll Tandem Switchboard
▪ Reduction of Noise in Cables by Electrolytic Condensers
▪ Short Cuts in Drafting
Vol. 8, No. 111930-07-012.48 MB▪ Improvements in Radio Broadcasting Transmitting
▪ Key-Display Type Call Indicators
▪ Automatic Prevention of Trouble by Decoders
▪ Flutter Effect in Loading Coils
▪ Multiplying the Subscriber's Line
▪ Acoustical Characteristics of Movie Screens
▪ Apparatus for Step-by-Step Routine Tests
Vol. 8, No. 121930-08-012.55 MB▪ Microphonic Action in Telephone Transmitters
▪ A Regenerative Telegraph Repeater
▪ The Ultra-Violet Microscope
▪ A Rapid Record Oscillograph
▪ Springs for Telephone Apparatus
▪ Central-Office Lighting
▪ The Holding Time Recorder
▪ The Campaign Against Noise
Vol. 9, No. 11930-09-012.53 MB▪ The Dean of Telephone Engineers
▪ Carty—The Engineer and The Man
▪ John J. Carty—a Biographical Note
▪ Radio Transmission to South America
▪ Measuring Flutter in Loading Coils
▪ Age Hardening Lead-Calcium Alloys
Vol. 9, No. 21930-10-012.68 MB▪ The Role of Barium in Vacuum Tubes
▪ Radio-Telephone Equipment for Airplanes
▪ New Radio Transmitters for Airway Applications
▪ Aircraft Radio Receivers
▪ Test Truck for Aircraft Radio
▪ Glow Discharge Lamps for Television System
▪ A Standard Test Set for Vacuum Tubes
▪ New Insulation Now in Production
Vol. 9, No. 31930-11-012.80 MB▪ Effect of Magnetic Interference on Relay Operation
▪ Automatic Display Call Indicator System
▪ A New Analyser of Speech and Music
▪ Reducing Wear at Base-Metal Contacts
▪ Panel Selectors
▪ Key Pulsing for No. 3 Toll Boards
▪ Function of Repeating Coils in Carrier Circuits
Vol. 9, No. 41930-12-012.38 MB▪ A New "B" Board for Panel Offices
▪ A Magnetization-Curve Tracer
▪ Cross-Fire Neutralization of Telegraph Circuits
▪ Finishes on the Metal Parts of Telephone Apparatus
▪ Power for Magneto Offices
▪ Common Frequency Broadcasting Development
▪ Ringing Conditions on PBX Trunks and Tie Lines
Vol. 9, No. 51931-01-012.23 MB▪ Telephone-Typewriter PBX Systems
▪ Selector-Connectors for PBX Service
▪ Economics of the Application of Relays to Telephone Circuits
▪ Electrical Delay Circuits for Radio Telephony
▪ Circuit Equipment for Program Transmission
▪ Step-by-Step Pulse Repeater
▪ A Shallow Horn for Theatre Use
Vol. 9, No. 61931-02-012.60 MB▪ Progress in Two-Way Television
▪ Early Manual Switchboard Development
▪ Telegraph Ground-Potential Compensator
▪ Testing Earth Anchors
▪ Telephone Jacks
▪ Telephone Order Wires for Toll Circuit Maintenance
▪ Maintenance of Tripping Relays
Vol. 9, No. 71931-03-012.35 MB▪ New Types of Photoelectric Cells
▪ Measuring Reverberation
▪ Life Testing of Vacuum Tubes
▪ A Small Call Indicator
▪ Damping Methods for Electrical Reproducers
▪ Theatre System for the Hard of Hearing
▪ Correct Time by Telephone
Vol. 9, No. 81931-04-012.65 MB▪ Sir Chandrasekhara Venkata Raman, Nobel Laureate
▪ Quality of Television Images
▪ A Trial of the Radiotelephone in Alaska
▪ Lamp Sockets
▪ More Phonograph Records Illustrating Distortion
▪ New Sound Reproducing Equipment for Theatres
▪ Washouts
▪ Saying it With Tones
Vol. 9, No. 91931-05-013.03 MB▪ An Address: Walter S. Gifford
▪ Key West-Havana Cable No. 4
▪ Carrier Equipment for Key West-Havana Cable
▪ Paragutta
▪ A Wear Test for Finishes
▪ Acoustic Delay Circuits
▪ A Loud Speaker Good to Twelve Thousand Cycles
▪ A New Type of Laboratory Bench
Vol. 9, No. 101931-06-016.04 MB▪ Dielectric Properties of Matter
▪ A-C Busy Lamps for Toll Boards
▪ Molded Insulating Materials
▪ New Laboratories for Telegraph and Carrier Telephone Development
▪ Inductive Coordination Laboratory
▪ What the Sender Test Circuit Does
▪ A Universal Turret for Desk Mounting
Vol. 9, No. 111931-07-012.55 MB▪ Radio's Past and Future
▪ The High Vacuum Tube Comes Before the Supreme Court
▪ Welded Steel Cases for Loading Coils
▪ The Panel System
▪ Field Laboratory for Outside-Plant Studies
▪ Dielectric Properties and Chemical Constitution
Vol. 9, No. 121931-08-012.71 MB▪ Dial Offices for Small Communities
▪ Recording Contour Gauge
▪ A Linear Time Axis for a Cathode-Ray Oscillograph
▪ "—And the Operator Will Answer"
▪ Repeaters for Two-Wire Toll Circuits
▪ Measuring the Frequencies of Radio Signals
▪ Automatic Testing Equipment for Trunk Circuits
Vol. 10, No. 11931-09-013.95 MB▪ New Permalloys
▪ Four-Wire Telephone Circuits
▪ Non-Ferrous Alloys
▪ Profile Lathe for Miniature Work
▪ A Fruitful Application of Mathematics
▪ Radiator Cooling Units for Reserve Power Plants
▪ Highway Wiring Diagrams
Vol. 10, No. 21931-10-012.63 MB▪ Measuring One Trillionth of an Atmosphere
▪ The Single-Line Telegraph Repeater
▪ A Small Subscriber Set
▪ Telephone Apparatus for the Hard of Hearing
▪ Portable Speech-Input Equipment
▪ The Panel Bank
▪ Police of New York State Adopt the Teletypewriter
p. 51 blurry
Vol. 10, No. 31931-11-011.74 MB▪ New Overseas Radio-Telephone Extensions
▪ A Versatile Nomogram for Circuit Problems
▪ Rolling Joints
▪ Interference Effects with Shared-Frequency Broadcasting
▪ Service Insurance for Toll Cord Circuits
▪ Shielding for Electric Circuits
▪ Squares and Rectangles
▪ The Golden Section
Vol. 10, No. 41931-12-011.71 MB▪ An Introduction to the Panel System
▪ A New Oscillator for Broadcast Frequencies
▪ Addressing Atlantic City Conventions
▪ The Sequence Switch
▪ Reduction of Radio Interference from Telephone Power Plants
▪ A 24,000 Watt Filter
▪ The Toll Train
Vol. 10, No. 51932-01-012.37 MB▪ The Time Factor in Telephone Transmission
▪ Nation-Wide Teletypewriter Service
▪ Coal for Transmitters
▪ An Adjustable Frequency Generator for the Voice Range
▪ Hydrogenized Iron of High Permeability
▪ Mortar Bandage Conduit Joints
▪ The Lapel Microphone
▪ Portable Balance Unit for A-C Precision Bridge
Vol. 10, No. 61932-02-012.47 MB▪ An Improved Transmitter for Operators' Use
▪ Distributing Programs in the Waldorf Astoria
▪ Quartz Crystal Resonators
▪ Coal Talks
▪ A Transmitter for the Coast Guard
▪ A New Retardation Coil for Composite Sets
▪ Power Driven Maintenance Tools
▪ Busy Indicators in the Manual System
Vol. 10, No. 71932-03-011.97 MB▪ Corrosion of Iron
▪ Printing the Test-Board Instructions
▪ Mechanically Locking Keys
▪ Switchboard Lamps
▪ Measuring the Illumination From Switchboard Lamps
▪ A Re-recording Machine for Sound Films
▪ Laboratory for Precision Linear Measurements
▪ Testing for Magnetic Characteristics
Vol. 10, No. 81932-04-012.23 MB▪ Pulp—The New Cable Insulation
▪ Smaller and Better Condensers
▪ The Mendham Laboratory
▪ A Push-Button Key for Train Dispatching
▪ Improved Continuity Test for Enamel Insulation on Wires
▪ The Horizontal Diamond-Shaped Antenna
▪ Transmission Networks and Their Measurement
Vol. 10, No. 91932-05-014.73 MB▪ Laboratory for Welding Studies
▪ Do Our Ears Grow Old?
▪ A Sensitive Moving-Coil Microphone of High Quality
▪ Adapting the Moving-Coil Microphone to Commercial Use
▪ Mountings, Connectors, and Amplifier for Moving-Coil Microphone
▪ The Service of Analytical Chemistry to Research
▪ A Portable Sound Meter
Vol. 10, No. 101932-06-011.79 MB▪ What is a Satisfactory Hearing Aid?
▪ Transmission Instruments for the New Audiophone
▪ Pacific Gas and Electric Extends Its Carrier System
▪ Transformer Equipment for Large Experimental Radio-Telephone Transmitter
▪ Audiphones
▪ Motion Pictures in Relief
▪ Acoustical Society Hears New Vertical Recordings
Vol. 10, No. 111932-07-011.56 MB▪ Electrical Reflections and Their Measurement
▪ A Low-Frequency Oscillator
▪ Summer Ailments and Their Treatment
▪ Portable Maintenance Tools for Commutators of Generators
▪ The Station Ringer
▪ A New System of Sound Recording
▪ A Measure of Physical Quality for Central Office Equipment
▪ Western Electric Photomatic Equipment
Vol. 10, No. 121932-08-011.83 MB▪ Boundary Lubrication
▪ A Permanent-Magnet Light Valve
▪ Portable Sound-Picture System for Sixteen Millimeter Film
▪ Wires for Subscribers' Premises
▪ Dial Services for Small Communities
▪ A New Switching Unit for Program Circuits
Vol. 11, No. 11932-09-012.15 MB▪ Order Turret No. 3
▪ A Tone Alternator
▪ Proving Grounds for Telephone Poles
▪ A Splash-Proof Dial for the Navy
▪ Airport Radio Transmitter
▪ A Radio Transmitter for the Itinerant Flyer
Vol. 11, No. 21932-10-013.82 MB▪ Radiation-Cooled Power Tubes for Radio Transmitters
▪ A Low-Power Broadcast Transmitter
▪ Solder and the Art of Wiping Cable Splices
▪ Testing the Elasticity of Vacuum Tube Filaments
▪ A Crosstalk Measuring Set of Improved Precision
Vol. 11, No. 31932-11-012.28 MB▪ A Telephone System for Harbor Craft
▪ Forecasting the Behavior of Wood Preservatives
▪ Commercial Construction Adopted for Ringing-and-Coin-Control Generators
▪ Fishing Industry Adopts Marine Telephony
▪ The Development of the Protector Block
▪ Cellulose Acetate Treatment of Textile Insulation
Vol. 11, No. 41932-12-012.20 MB▪ A New Common-Battery Board for Small Offices
▪ Generating High Frequencies with Precision
▪ A Precise Radio-Frequency Generator
▪ A Skin-Effect Phenomenon
▪ A Frequency Monitoring Unit for Broadcast Stations
▪ Transmission Lines for Short-Wave Radio Systems
Vol. 11, No. 51933-01-012.23 MB▪ Evaluating Hearing Aids
▪ Music Wire Springs
▪ A Heterodyne Oscillator of Wide Frequency Range
▪ Combating Rust With Metallic Finishes
▪ Measuring Microphonic Noise in Vacuum Tubes
▪ Bus Announcing Outfits
Vol. 11, No. 61933-02-012.35 MB▪ A "Low-Hum" Vacuum Tube
▪ An Improved Wheatstone Bridge for Toll Test Boards
▪ Supplying Atmospheres of Known Humidity
▪ Light-Weight Transformers for Aircraft
▪ Portable Long Wave Testing Apparatus
▪ A Circuit for Measuring Longitudinal-Circuit Unbalance at High Frequencies
Vol. 11, No. 71933-03-012.06 MB▪ The Deformation of Matter
▪ Tuned-Transformer Coupling Circuits
▪ Mounting Quartz Plates
▪ A Radio Distribution System for Apartment Buildings
▪ A New P.B.X. for Large Establishments
▪ Power Equipment Laboratory
Vol. 11, No. 81933-04-012.22 MB▪ Measuring and Recording Low Humidities
▪ A Mercury Jig for Testing Toroidal Cores
▪ Experimental Paint and Varnish Compounding
▪ The New Oscillators for the Radio Frequency Range
▪ Loud Speakers Summon Physicians in the New York Hospital
▪ A New Service for Residents
▪ The Underwriters' Laboratories
Vol. 11, No. 91933-05-012.32 MB▪ The Reproduction of Orchestral Music in Auditory Perspective
▪ New Radio Telephone Equipment for Transport Airplanes
▪ A Three-Frequency Radio Telephone Transmitter for Airplanes
▪ A Crystal Control Superheterodyne Receiver
▪ Artificial Anthracite
Vol. 11, No. 101933-06-012.08 MB▪ An Acoustic Illusion Telephonically Achieved
▪ A Compression Test for Soft Solids
▪ Uses of Filters in Carrier Systems
▪ Mushrooms and Maintenance
▪ Delayed Speech
▪ Improved Current Control for Low Range Meter Calibration
Vol. 11, No. 111933-07-013.59 MB▪ The Panel Dial System
▪ A Stroboscope for Checking the Speed of Subscribers' Dials
▪ The Bell System Exhibit at the Century of Progress Exposition
▪ A Sensitive Method of Measuring Corrosion
▪ Soft Rubber Earpiece for the Audiphone
▪ Charging Batters Without a Generator
Vol. 11, No. 121933-08-012.73 MB▪ Harold de Forest Arnold
▪ Seeing Sound at the Chicago Exposition
▪ Radio Telephone Communication with the Caribbean Countries
▪ Voice Frequency Control Terminals for Caribbean Radio Systems
▪ The 13A—A Radio Receiver for Diversified Uses
▪ A Radio Transmitter for Central American Service
Vol. 12, No. 11933-09-012.42 MB▪ Filters in Action
▪ Direct Current Conduction in Dielectrics
▪ Water at West Street
▪ Gases in Metals
▪ A Current Transformer for Low Radio Frequencies
▪ Fuses
Missing pp. 20-21
Vol. 12, No. 21933-10-014.20 MB▪ The Caesium-Oxygen-Silver Photelectric Cell
▪ Electrical Leakage Over Glass Surfaces
▪ Differential Pitch Sensitivity of the Ear
▪ Wetting of Solids by Liquids
▪ A One-Pair Loaded Emergency Cable
▪ Moisture-Proofing Transmitters with Rubber
▪ The 80A Amplifier
Vol. 12, No. 31933-11-011.74 MB▪ Ultra-Short-Wave Transmission
▪ X-Ray Examination for Metal Defects
▪ Measuring Inductance with a Resistor
▪ An Artificial Ear for Receiver Testing
▪ An Artificial Voice for Transmission Studies
▪ Amplifying Watch Sounds
▪ Evaluating Arc Resistance of Insulating Materials
Missing pp. 74-75
Vol. 12, No. 41933-12-011.88 MB▪ A 100 Kilowatt Vacuum Tube
▪ Lubricating Brushes for M-Type Generators
▪ Weatherproofing of Telephone Wires
▪ Equalizers In Open-Wire Carrier Circuits
▪ Minimizing Modulation in Transformers
▪ Telephone Manufacturing Information
Vol. 12, No. 51934-01-011.88 MB▪ Permanent Magnets
▪ First Aid Kits and Facts
▪ Entrance Cables for Carrier Toll Circuits
▪ Distributing Toll Tickets by Pneumatic Tubes
▪ Moving the Toll Ticket
▪ Long Distance Telegraph Circuits
Vol. 12, No. 61934-02-011.41 MB▪ Open-Wire Program Circuits
▪ Line Filters for Open-Wire Program Circuits
▪ Resistance Lamps
▪ A Continuously Adjustable Band Pass Filter
▪ Testing the Life of Dial Apparatus By Machines
▪ A Self-Contained Bridge for Measuring Both Inductive and Capacitive Impedances
▪ A Mathematical Theory of Rational Inference
Missing pp. 68-69
Vol. 12, No. 71934-03-013.26 MB▪ Auditory Perspective
▪ Auditorium Acoustics and Control Facilities for Reproductions in Auditory Perspective
▪ Loud Speakers and Microphone for Auditory Perspective
▪ Long Distance Transmission for Auditory Perspective
▪ Pounds of Prevention—Gas-Filled Cables
▪ Western Electric Noiseless Recording
Vol. 12, No. 81934-04-011.60 MB▪ Audio-Frequency Atmospherics
▪ How Sharply Can a Metal Part Be Bent?
▪ Regulation of Central-Office and Tie-Trunk Service in Private Branch Exchanges
▪ Reproduction of Pencil-on-Paper Drawings by Mechanical Means
▪ Surveying in Curbed Spaces
▪ Measurement of Transmission Loss Through Partition Walls
▪ The Oxidation of Organic Substances
Missing pp. 238-239
Vol. 12, No. 91934-05-011.58 MB▪ New Airport Receivers
▪ A Highly Selective Weather and Beacon Radio Receiver for Airplane Use
▪ Remote Tuning Controls for Aircraft Radio Receivers
▪ Articulation Testing
▪ Automatic Articulation Testing Apparatus
▪ Adapting the Telephone Repeater to Train Dispatching
▪ Vitamin B
Vol. 12, No. 101934-06-011.62 MB▪ Feedback Amplifiers
▪ A Telephone for Use in Explosive Atmospheres
▪ Testing in Explosive Atmospheres
▪ The Direction of Arrival of Radio Waves
▪ Neutralizing Disturbance Voltages in Communication Circuits
▪ Winding Silica Springs
Vol. 12, No. 111934-07-011.91 MB▪ Early Handsets
▪ Joints in the Insulation of Submarine Cable
▪ Maintaining Quality in Bell System Dry Batteries
▪ No. 8 Test and Control Board
▪ Jacks and Plugs for Portable Telephones
▪ A 5000-Volt Mercury-Vapor Rectifier for the 6B Radio Broadcasting Transmitter
Vol. 12, No. 121934-08-011.39 MB▪ Trunking as a Problem of Probability
▪ Standardizing Basic Electrical Units
▪ Dissipation Constants in Solids
▪ Toll Transmission Measuring System for the No. 8 Test and Control Board
▪ The Electrical Constants of the Ground
▪ Retardation Coils for Precision Filters
▪ Adjusting Precision Filters
Vol. 13, No. 11934-09-011.84 MB▪ Speech Input Equipment for Radio Broadcasting
▪ Iron-Cobalt Alloys
▪ Testing Cable Sheath for Fatigue
▪ A Portable Oscilloscope
▪ The Trunk Group Busy Register
▪ The Switchboard Cord
▪ An Improved Bend Tester
Vol. 13, No. 21934-10-011.38 MB▪ An Extension of Land Telephone Lines by Ultra-Short Wave Radio
▪ Magnetic Materials
▪ Diffusion of Water Through Organic Insulating Materials
▪ The Regulation of Transmission Over Open-Wire Lines at Carrier Frequencies
▪ Acoustic Spectrometer
Vol. 13, No. 31934-11-012.15 MB▪ Some Principles of Transposing Open-Wire Lines
▪ The Nature of Water Adsorbed on Cellulose
▪ A High-Speed Level Recorder for Acoustic Measurements
▪ At the America's Cup Races
▪ Microanalysis
▪ Gas-Filled Thermionic Rectifiers
Vol. 13, No. 41934-12-011.95 MB▪ The Voice-Operated Compandor
▪ The Lineman's Leather Lifeline
▪ Spot Welding
▪ Observing the Corona
▪ The Holmdel Laboratory
▪ An Improved Volume Indicator
Vol. 13, No. 51935-01-012.17 MB▪ Loudness and Pitch
▪ High Frequency Resistance Standard
▪ Evaluation of Organic Finishes
▪ The Six-String Oscillograph
▪ Galvanometry in Vacuo
▪ A Portable Public Address System
Missing pp. 136-137
Vol. 13, No. 61935-02-011.63 MB▪ Disturbances in Radio Transmission
▪ The New Telephotograph System
▪ Vacuum Tubes at Very High Frequencies
▪ Trials of New Wide-Band Program Circuits
▪ A Wire-Wound Grid Resistance
▪ A High Precision Speed Regulator
Vol. 13, No. 71935-03-012.23 MB▪ The Ionosphere
▪ A Mirror for the Voice
▪ An Adjustable Oscillator of High Precision
▪ Insulation Resistance of Cotton
▪ Heat Treatment
▪ Depicting Currents in Telephone Lines
Vol. 13, No. 81935-04-011.92 MB▪ A 50-KW Radio Transmitter of High Fidelity
▪ Controlled Radiation for Broadcasting
▪ Calling by Whistle
▪ A High-Voltage Relay
▪ Primary Toll Test Boards
▪ Universal Alignment Chart
Vol. 13, No. 91935-05-012.16 MB▪ Mechanical Analysis of Waves
▪ A Telephone Set for Outdoor Use
▪ A General-Purpose Frequency Analyzer
▪ A Small Radio Transmitter for Police Duty
▪ A Bridge for Measuring Small Phase Angle
▪ Conduit Plugs
▪ Characteristics of Western Electric Vacuum Tubes
Vol. 13, No. 101935-06-011.86 MB▪ A Police Radio System for Newark
▪ A Recording Transmission Measuring Set
▪ A Marine Radio Compass
▪ Quartz Crystal Filters
▪ Dryness in Telephone Cables
Vol. 13, No. 111935-07-011.67 MB▪ Coaxial Conductor Systems
▪ Projecting Circuit Performance on a Screen
▪ Recent Advances in Microphonic Research
▪ Measuring Displacements of Microphone Contacts
▪ Short-Wave Programs for Waldorf Guests
▪ Holding the Ticket
Vol. 13, No. 121935-08-011.76 MB▪ The Barkhausen Oscillator
▪ Balancing Crosstalk in Toll Cables
▪ A Bone-Conduction Receiver for the Audiphone
▪ The Bridged T Equalizer
▪ A High-Quality Broadcast Transmitter of Medium Power
▪ A New Vacuum Tube for Ultra-High Frequencies
Vol. 14, No. 11935-09-012.15 MB▪ Control of Alignment of Sequence Switch Drives
▪ Two Types of Dielectric Polarization
▪ Two-Way Police Radio System
▪ A Mobile Transmitter for the Ultra-High Frequencies
▪ The Dielectric Behavior of Camphor
▪ Heat Treatment in Magnetic Fields
▪ Impact Tester for Moulded Insulating Materials
Vol. 14, No. 21935-10-011.93 MB▪ A Non-Directional Microphone
▪ Hysteretic Modulation
▪ Telegraph Testing Facilities
▪ A Speech Amplifier for Police Radio
▪ Centrifugal Type Voltage Regulators
▪ Quiet Amplifier Tubes
▪ Carrier Frequency Heterodyne Oscillator
▪ Soldering Lead Cable Electrically
▪ An Ultra-High-Frequency Radio Receiver for Police Use
Missing pp. 58-59
Vol. 14, No. 31935-11-014.96 MB▪ Vacuum Tube for Small Current Measurements
▪ Acoustical Test Chamber With Cloth Walls
▪ Under-Rug Telephone Cordage
▪ A Radio Beacon Transmitter for WOR
▪ Soft Solders
▪ A Test Car for Marine Radio Telephone Surveys
▪ High-Fidelity Radio Transmitter for Ultra-High Frequencies
Vol. 14, No. 41935-12-012.27 MB▪ Earth Current Measurements
▪ Propagation of Ultra-Short Radio Waves
▪ Preparing Metals for Microscopy
▪ Wind From Quartz Crystals
▪ Radio Bridges Hurricane Break
▪ Measuring Inductance of Coils With Superimposed Direct Current
▪ A Radio Transmitter for the Private Flyer
▪ A Bend Tester for Vacuum Tube Wires
Missing pp. 128-129
Vol. 14, No. 51936-01-011.74 MB▪ Novel Design Adapts 3A TWX to Wide Range of Conditions
▪ The 307A Power Pentode
▪ Measuring Delay on Picture-Transmission Circuits
▪ An Adjustable Precision Standard of Phase Difference
▪ A Radio Receiver for the Private Plane
▪ A Radio Compass for Aircraft
▪ Transformer Testing Laboratory
Vol. 14, No. 61936-02-012.10 MB▪ The Telephotograph Line
▪ New Carrier Loading Equipment for Entrance Cables
▪ Secretarial Service
▪ Delay Equalizers for Telephotograph Transmission
▪ "Balance" in Railroad Dispatching Circuits
▪ Locating Toll-Cable Faults
Vol. 14, No. 71936-03-012.37 MB▪ Electron Diffraction Analysis
▪ Paint Films of Controlled Thickness
▪ Testing Problems in Outside Plant Development
▪ Direction of Motion of Oscilloscope Spot
▪ Sound System for Program Distribution
▪ A Theory of Shielding
▪ Measurements of Noise on Program Circuits
▪ Improved Transmission-Measuring System
▪ An Inexpensive Thousand-Cycle Generator
▪ A Submarine Loading Case
Vol. 14, No. 81936-04-012.14 MB▪ Elastic Vibrations of Quartz
▪ Dialing Ships at Sea
▪ Lead Sleeve Cases for Loading Coils
▪ High Permeability and Plastic Flow in Magnetic Fields
▪ An Electrical Stethoscope for the General Pratitioner
▪ Life Test Recorder
▪ Field Trial for New Two-Wire Toll Circuits
Vol. 14, No. 91936-05-011.93 MB▪ Electric Wave Guides
▪ A "Hit" Suppresor
▪ Amplitude Compression in Long Telephone Circuits
▪ New Telephone Booth
▪ Testing for Air Contamination in Manholes
▪ Studies of Single-Sideband Short-Wave Transmission
▪ A Broadcast Frequency Measuring Set
▪ A Telephone As a Conference Aid
Vol. 14, No. 101936-06-011.62 MB▪ Effect of Electric Shock on the Heart
▪ High-Fidelity Radio Broadcasting
▪ Adhesives
▪ A New Power Amplifier of High Efficiency
▪ X-Ray Diagnosis for Telephone Apparatus
▪ An Acoustic Resistance Meter
Vol. 14, No. 111936-07-011.79 MB▪ Multi-Frequency Radio Transmitter
▪ Reforming Telegraph Signals
▪ Automobile Finishes
▪ The 300A Vacuum Tube
▪ Transmission Improvements in Telegraph Loop Circuits
▪ Insuring Quality in Tapes
Vol. 14, No. 121936-08-011.65 MB▪ Dowsing for Cable
▪ The Grounded Vertical Radiator
▪ A One-Tube Carrier System
▪ Mathematics and Electrical Communication
▪ The 86 Type Amplifier
▪ A Single-Sideband Short-Wave Receiver
Vol. 15, No. 11936-09-012.50 MB▪ An All-Purpose Radio Receiver for Mobile Applications
▪ Teletypewriter Exchange Systems
▪ Molecular Rotation in Organic Crystals
▪ Out-of-Block Protector
▪ Directive Antenna Solves Coverage Problem
▪ Telephone Hand Tools
▪ New Reproducer System for Small Theatres
▪ The Impinger
Vol. 15, No. 21936-10-012.89 MB▪ Rubber Research
▪ Determining Circuit Characteristics at Low Frequencies
▪ Developing the 106A1 Regenerative Telegraph Repeater
▪ Remote Control for Radio Receivers
▪ Automatic Comparator for Characters on Perforated Teletypewriter Tape
▪ Automatic Measurement of Transmission
Vol. 15, No. 31936-11-012.06 MB▪ Buried Telephone Wire
▪ A New 5-kw Broadcast Transmitter
▪ A Machine for Testing Enameled Wire
▪ Copper Oxide Rectifiers for Telephone Power Supply
▪ Apparatus Card Catalog
▪ Relaxation Time in Dielectrics
▪ Protecting Communication Circuits at Power Stations
Vol. 15, No. 41936-12-013.20 MB▪ Synthesizing Speech
▪ A Metallographic Microscope of Exceptional Power
▪ Impact Tester for Organic Finishes
▪ Vacuum Tube Improves Selective Ringing
▪ The 313A Vacuum Tube
▪ Tonlars
▪ A Wide-Range Oscillator for the Higher Frequencies
▪ Protection Against Lightning Interference
▪ Laminated Phenolic Insulating Materials
▪ "The Renaissance of Physics"
Vol. 15, No. 51937-01-012.65 MB▪ Talking Battery
▪ How Pitch Changes with Loudness
▪ Non-Spreading Lubricating Oils
▪ Apparatus Specifications
▪ New Carrier System Filters
▪ A Modernized Hearing Meter
▪ Decibel Meters
▪ A New Chair for Operators
Vol. 15, No. 61937-02-012.21 MB▪ A Half-Meter Tube
▪ Stabilized Feedback for Radio Transmitters
▪ Measuring the Plating on Screw Threads
▪ Remagnetizer for Ringer Magnets
▪ A Telegraph Signal Biasing Set
▪ Paper Insulation in Telephone Construction
▪ Mercury Switch for Telephone Booths
▪ A Watch-Rate Recorder
Vol. 15, No. 71937-03-012.06 MB▪ Modulation in the G-1 Carrier System
▪ Around-the-World Radio Echoes
▪ Fields Caused by Remote Thunderstorms
▪ Sound Reinforcing System for Hollywood Bowl
▪ A New Timing Motor for Oscillographs
▪ Measuring Loudspeaker Response Automatically
▪ Thin Crystals
Vol. 15, No. 81937-04-012.72 MB▪ Broad-Band Carrier Systems
▪ Measurement of Attenuation at High Frequencies
▪ A New Noise Meter
▪ A New Message Register Camera
▪ A 5-Megacycle Impedance Bridge
▪ Applying Solderless Cord Tips in the Field
▪ A New Ring for Distributing Frames
Vol. 15, No. 91937-05-011.56 MB▪ The Coaxial Cable System
▪ A Noise Reducer for Radio-Telephone Circuits
▪ Conditioning Insulating Materials for Test
▪ Telephotograph Transmitter and Receiver
▪ Terminal Equipment for Telephotography
▪ Regulated Plate Supply
Vol. 15, No. 101937-06-011.66 MB▪ Loudness Measurements
▪ Volume Limiter Circuits
▪ A Line-Busy Recorder
▪ The Surface Wave in Radio Transmission
▪ Construction of the Coaxial Cable
▪ Installing the Coaxial Cable
Vol. 15, No. 111937-07-014.66 MB▪ The Crossbar Switch
▪ A Power Amplifier Tube for Ultra-High Frequencies
▪ Rectifier for Telephone Power Supply
▪ A High-Quality Headset for Monitoring
▪ Carrier for Coaxial Groups
▪ Group Terminal for the Coaxial System
Missing pp. 361-362
Vol. 15, No. 121937-08-012.36 MB▪ 101-Type Key Equipments
▪ Crosstalk Measurements
▪ A Diverter-Pole Generator for Battery Charging
▪ Repeaters for the Coaxial System
▪ High-Frequency Supply for Degassing
Vol. 16, No. 11937-09-012.04 MB▪ Magnetic Recording and Reproducing
▪ Eddy Current Shielding in Laminated Cores
▪ New Tubes for Carrier Systems
▪ Quartz Plates for Frequency Sub-Standards
▪ Vibration Studies with the Rapid Oscillograph
Missing pp. 12-15
Vol. 16, No. 21937-10-011.62 MB▪ The 1A Teletypewriter Switchboard
▪ Equivalent Networks for Negative-Grid Triodes
▪ Supplying Power to Central Offices
▪ An Ultra-Short Wave Circuit for Palomar Observatory
▪ Diphonic Loudspeaker for Mirrorphonic Sound Systems
▪ Limitations in High-Frequency Band Filter Design
▪ A Multi-Channel Radio Monitoring System
▪ High Dispersion X-Ray Spectrometer
Vol. 16, No. 31937-11-014.34 MB▪ The Type-H Carrier Telephone System
▪ Low-Cost Microphone for Varied Application
▪ Non-Corroding Rubber Insulation for Telephone Cords
▪ A Filter for Airway Range Systems
▪ An Inexpensive Bridge for Capacitance and Conductance Measurements
▪ Open-Wire Line Losses
▪ High-Frequency Attenuator
▪ Vapor-Pressure Humidostat and Thermostat
Vol. 16, No. 41937-12-011.59 MB▪ Coaxial Cable System Transmits Motion Pictures
▪ New Cathode-Ray Tubes
▪ Variation of Cable Loss with Temperature
▪ Transmission Line Structures as High-Frequency Networks
▪ Pressure Cleaning
▪ Forecasting Sunspots and Radio Transmission Conditions
▪ The Isograph—A Mechanical Root-Finder
▪ The Mechanism of the Isograph
▪ Conductance in Telephone Cables
Vol. 16, No. 51938-01-011.89 MB▪ Principles of the Musa
▪ Musa Apparatus
▪ Automatic Adjustments in Radio-Telephone Control Terminals
▪ A New Micrometer Ratchet
▪ Aluminum Alloy Structural Materials
▪ The Teletypewriter Exchange Network
▪ The No. 5 Teletypewriter Switchboard
▪ Higher Volumes Without Overloading
▪ A Volume-Limiting Amplifier
Vol. 16, No. 61938-02-011.97 MB▪ Television Over the Coaxial Cable
▪ Transmission Characteristics of the Coaxial Structure
▪ An Anti-Static Loop for Aircraft
▪ The Musa from the Outside
▪ The Carrier Telephone Alphabet
▪ Noise Measurements and the International Conference on Acoustics
Missing pp. 210-211
Vol. 16, No. 71938-03-011.73 MB▪ Applying the Type-H Carrier Telephone System to Railroads
▪ Hearing Impairment and Sound Intensity
▪ Higher Magnetic Permeabilities
▪ Experimental Results from the Musa
▪ Permanent Magnet Machines for Telephone Offices
▪ Power Supply for the Coaxial Repeaters
▪ Stability of Reception at Two Meters
▪ Noise Protection for Voice-Operated Devices
▪ Protective Circuits for Antenna-Coupling Networks
Vol. 16, No. 81938-04-011.58 MB▪ Broad-Band Carrier System for Cables
▪ Steel in the Telephone Plant
▪ A Multi-Frequency Transmitter for the Private Plane
▪ Improved Methods in Cable Testing
▪ High-Speed Motion-Picture Photography
▪ New Magnetic Telephone
▪ Precise Measurement of Insertion Phase Shift
▪ A Recording System for Transmission Measurements
▪ Console-Type Speech-Input Equipment
Vol. 16, No. 91938-05-011.72 MB▪ The U-Type Relay
▪ Electron Multiplier Design
▪ The Y-Type Relay
▪ Channel Terminal Equipment for Broad-Band Carrier Systems
▪ Time Lag in Gas-Filled Photoelectric Cells
▪ Laboratory Tests of Wood Preservatives
Vol. 16, No. 101938-06-011.55 MB▪ The Crossbar Switch in the 755 PBX
▪ The 755 PBX
▪ An Inductance and Capacitance Bridge
▪ Making Broadcast Synchronization Easy
▪ Short-Circuiting Relay Protectors
▪ Design Features of Short-Circuiting Relay Protectors
▪ Oscillating Crystal
▪ A New Coastal Marine Radio Telephone Set
Vol. 16, No. 111938-07-011.76 MB▪ Carrier Supply for Type K Systems
▪ Paper as a Medium in Microanalysis
▪ Experiments on Talking Contacts
▪ A Voice-Operated Return-Loss Measuring Set
▪ A Teletypewriter Switchboard for Private Line or PBX Service
▪ The 281A Program Line Panel
▪ Gas Tube Voltage Recorders
▪ Tool Kit for Teletypewriter Maintenance
Vol. 16, No. 121938-08-012.00 MB▪ Rubber-Insulated Station Cords
▪ Acoustic Delay Circuits for Laboratory Use
▪ Acoustic Attenuators
▪ Improvements in Relay Coil Insulation
▪ Reducing Disturbances Produced on Telephone Circuits by Power Rectifiers
▪ Lifting a Finger Against Noise
▪ Pilot-Wire REgulators for Voice-Frequency Cable Circuits
Vol. 17, No. 11938-09-012.36 MB▪ A 50-KW Broadcast Transmitter
▪ Improved Design for Five-Kilowatt Broadcast Transmitter
▪ Electron Analysis of Stearic Acid Films
▪ Charging Control for PBX Batteries
▪ Simplified Balancing Networks for Toll Cables
▪ A Radio Telephone Set for Small Vessels
▪ Regulated Tube Rectifiers Using Magnitude Control
▪ Grid-Controlled Rectification Used in Small 48-Volt Power Plant
Vol. 17, No. 21938-10-011.76 MB▪ Noise Prevention in Telephone Circuits
▪ A Call-Thru Test Set
▪ Suppressor-Grid Modulation
▪ Filters for H-1 Carrier Telephone System
▪ A Vogad for Radio-Telephone Control Terminals
▪ General Features of Teletypewriters
▪ Magnetizing by Condenser Discharge
▪ Channel Crystal Filters for Broad-Band Carrier Systems: Electrical Features
▪ Channel Crystal Filters for Broad-Band Carrier Systems: Physical Features
Vol. 17, No. 31938-11-011.47 MB▪ Drying Cable Splices by Desiccants
▪ 22A Radio Transmitter
▪ Time Intervals in Telephone Conversation
▪ The New 94-Type Bridging Amplifier
▪ Magnetic Shields
▪ Magnetic Shields for Transformers
▪ Tne No. 4 Order Turret
Vol. 17, No. 41938-12-011.45 MB▪ Spacing of Telephone Wires
▪ Ringing Power for Large Offices
▪ Four-Wire Circuits in Retrospect
▪ High-Frequency Attenuation on Open-Wire Lines
▪ Improved Program and Line Amplifiers for the Broadcast Studio
▪ Distributing Time Announcements
Vol. 17, No. 51939-01-011.93 MB▪ Generation of Reference Frequencies
▪ Measuring Permeability Under Stress
▪ A Lighted Display Board for Crossbar Calls
▪ Repeaters for the Type-K Carrier System
▪ The 554A Tool
▪ Template for Graphing Audio-Amplifier Performance
▪ Identifying Cable Wires
▪ A Portable Telephone for Railroads
▪ Regulation for Type-K Carrier
Vol. 17, No. 61939-02-011.52 MB▪ Pedro the Voder—A Machine That Talks
▪ The Crossbar System
▪ Telephone Alarm Fuses
▪ Long-Distance Conference System
▪ Crosstalk Balancing for the Type-K Carrier System
▪ Crosstalk Poling for the Cable Carrier System
▪ Anti-Vibration Support for Sensitive Portable Galvanometers
▪ Portable Emergency Radio-Telephone Equipment
Vol. 17, No. 71939-03-011.45 MB▪ Spectrochemical Analysis
▪ Suppressing Noise and Crosstalk on the Type-K Carrier System
▪ Molded Telephone Apparatus Design
▪ Crossbar Trunking
▪ A New Telegraph Transmission Measuring Set
▪ New Test Set for Identifying Telephone Wires
Vol. 17, No. 81939-04-013.12 MB▪ Crossbar Senders
▪ Coördinated Induction Tests on an A-C Electrified Railroad
▪ 356A Vacuum Tube
▪ Power Plant for Broad-Band Repeater Stations
▪ Lockout in Long Telephone Circuits
▪ Sound-Level Distribution Recorder
▪ A New Page Teletypewriter
▪ A Small Pre-Mixing Amplifier
Vol. 17, No. 91939-05-012.33 MB▪ The Crossbar Line-Link Frame
▪ A Precision Clock for Telephone Time
▪ Extruded Lead Casings for Condensers
▪ Holding-Magnet Selector for Teletypewriters
▪ The Story of the 2B Regulator
▪ The 17B Oscillator
▪ A Longitudinal-Noise Filter for the Type-K Carrier System
▪ The Multi-Contact Relay
Vol. 17, No. 101939-06-012.40 MB▪ Noise at Telephone Locations
▪ Measuring Transmission Speed of the Coaxial Cable
▪ Television Pick-Up Over Telephone Cable Pairs
▪ An Automatic Power Plant for Toll Systems
▪ A Vacuum-Tube Testing Set for Carrier Systems
▪ A General-Purpose Electromagnet
▪ The Bell System at the New York World's Fair 1939
▪ Sender-Link and Controller Circuits
▪ Originating Markers
▪ A Radio Slide Rule
Vol. 17, No. 111939-07-011.27 MB▪ A Cardioid Directional Microphone
▪ Optical Properties of the Alkali Metals
▪ The Anti-Sidetone Station Circuit
▪ A Precise High-Frequency Inductometer
▪ Increasing the Range of Tripping Relays
▪ Number Decoding by Terminating Markers
▪ A Ringing Machine for Small Offices
▪ New Mobile Radio Equipment
Vol. 17, No. 121939-08-011.83 MB▪ Sorption of Water by Organic Insulating Materials
▪ Terminating Markers: Busy Testing and Line-Choice Selection
▪ Time Characteristics of the U-Type Relay
▪ Portable High-Frequency Transmission-Measuring Set
▪ Simplifying the Adjustment of Antenna Arrays
▪ Jacks for Main Distributing Frames
Vol. 18, No. 11939-09-011.35 MB▪ The Longitudinal Circuit
▪ The Ortho-Technic Audiphone
▪ The 710A Bone-Conduction Receiver
▪ Dialing Incomings
▪ A One-Kilowatt Broadcast Transmitter
▪ Lockout Circuits
▪ Optical Curve Analysis
Vol. 18, No. 21939-10-011.69 MB▪ Television Transmission Over Telephone Cables
▪ Crossbar Trunking Studies
▪ A Level Compensator for Carrier-Telegraph Systems
▪ Magnetic Materials Testing
▪ The Spark Chronograph
▪ Continuous Breakdown Test for Enameled Wire
▪ Beryllium Copper
Vol. 18, No. 31939-11-011.28 MB▪ Weather by Telephone
▪ Weather-Announcing Tape Machine
▪ An Artificial Mastoid for Audiphone Measurements
▪ A Remotely Controlled Radio Receiver
▪ Gas-Tube Noise Generator for Circuit Testing
▪ Single-Sideband Short-Wave Receiver
▪ Testing Shields for Carrier-Frequency Line Structures
▪ Remote Control of Radio Systems
Vol. 18, No. 41939-12-011.25 MB▪ Analysis of World's Fairs' Hearing Tests
▪ The 3B Toll Switchboard
▪ Measuring Lines for Program Transmission: I–The 19-Type Oscillator; II—The 13A Transmission-Measuring Set
▪ Field Tests of the Crossbar System
▪ Beat Notes in High-Frequency Calibration
▪ Operator-Training Facilities at Toll Switchboards
▪ The Vocoder
Vol. 18, No. 51940-01-011.72 MB▪ The Manahawkin Musa
▪ Equipment for the Demonstration Toll Call
▪ Automatic Cathode-Ray Oscillograph
▪ Radio Compass for Small Vessels
▪ Transpositions
pp. 132-133, 136-137, 140-141 missing
Vol. 18, No. 61940-02-011.61 MB▪ The Coronaviser
▪ Circuit Features of the 3B Toll Board
▪ Feedback Improves Electromechanical Recording
▪ The Exponential Transmission Line
▪ Frequency Modulation
▪ Magnetic Strain Gauge for Cable Sheath
▪ Effect of Extended Signaling Range for Subscriber Loops
▪ New Coils for Operators' Telephone Sets
▪ Laboratory Tests of the Crossbar System
Vol. 18, No. 71940-03-011.93 MB▪ A Demonstration of Guided Waves
▪ Crosstalk Balancing Coils for the Type-K Carrier System
▪ High-Speed Motion Pictures of the Human Vocal Cords
▪ The "Telephone Clock"
▪ Outside Plant Field Laboratory
▪ Improved Repeater Tubes
Vol. 18, No. 81940-04-011.36 MB▪ A Broad-Band Carrier System for Open-Wire Lines
▪ A Crosstalk Reference Standard
▪ Motor-Driven Switchboard Clock
▪ Crossbar Call-Indicator Pulsing
▪ Electron Diffraction Patterns of Silica and Aluminum Hydrate
▪ Dielectric Loss in Ice
▪ Code Ringing Supply for Community Dial Offices
▪ Metal Horns as Radiators of Electric Waves
▪ An Improved Loud-Speaking Telephone
▪ A Relay Chatter Meter
Vol. 18, No. 91940-05-011.76 MB▪ Stereophonic Recordings of Enhanced Music
▪ Stereophonic Reproduction From Film
▪ Intertoll Dialing With Step-by-Step Selectors
▪ Printing Techniques in Analytical Chemistry
▪ Electrographic Printing
▪ Audition Demonstration
▪ Contacts for Crossbar Apparatus
▪ Transmission Features of the Weather Announcement System
Vol. 18, No. 101940-06-011.46 MB▪ Hearing-Test Machines at the World's Fairs
▪ Terminal Circuits for the J Carrier System
▪ Telephone Facilities for Airport Traffic Control
▪ A Wiping Solder With Improved Handling Characteristics
▪ Spots on the Sun
▪ The "Vu" and the New Volume Indicator
▪ The 1A Key Telephone System
Vol. 18, No. 111940-07-011.52 MB▪ Varistors: Their Characteristics and Uses
▪ Cables for the J Carrier System
▪ Improvements in Drop Wire
▪ Television for National Republican Convention
▪ A Signalling System for Intertoll Dialing
▪ Sound Tests of Telephone Ringers and Dials
▪ Alarm System for Auxiliary Repeater Stations
Vol. 18, No. 121940-08-011.82 MB▪ The C5 Carrier System
▪ New Hysteresis Model
▪ The 14C Program Amplifier
▪ Transmission Measuring Set for Outlying Telegraph Stations
▪ Heavy-Water Rochelle-Salt Crystals
▪ A Loud-Speaking Telephone System
▪ Crosstalk Balancing in the J-Carrier System
▪ Determination of the Average Life of Vacuum Tubes
Vol. 19, No. 11940-09-012.34 MB▪ Fifteen Years
▪ The Nature of Organic Insulating Materials
▪ Six-Way Directional Microphone
▪ New Voice-Frequency Electrical Delay Network
▪ Unit Ventilator
▪ Synchronized FM Transmitter
▪ Toll Crossbar Call-Distributing System
▪ A Dialing Circuit of Increased Range
▪ Magnetic Ultra-Micrometer
Vol. 19, No. 21940-10-012.01 MB▪ A Telephone Set for Explosive Atmospheres
▪ Silicon Carbide Varistors
▪ The C5 Carrier Terminal
▪ J Carrier in the Field
▪ Universal Phonograph Reproducer
▪ Engineering an Improvement in Panel Clutches
▪ Testing the Behavior of Improved Panel Clutches
Vol. 19, No. 31940-11-011.24 MB▪ Regulation for the J-2 Carrier Telephone System
▪ Dielectric Properties of Pigmented Rubber
▪ Protecting Switchboard Lamps with Varistors
▪ Wire-Joining Methods
▪ A Bridge for Measuring Core Loss
▪ "A Modern Aladdin's Lamp"
▪ An Interpolation Method for Setting Laboratory Oscillators
Vol. 19, No. 41940-12-011.16 MB▪ Thermistors, Their Characteristics and Uses
▪ Devices for Combining DB Levels
▪ Analysis of Losses in Magnetic Cores
▪ "Information" in Less Space
▪ Carrier and Pilot Supply for the J2 Carrier System
▪ Metallic Bridges Between Contact Points
▪ A Coupling Unit for Telephotograph Transmission
▪ Measuring the Air Flow of Small Fans
Vol. 19, No. 51941-01-011.32 MB▪ Stevens Point-Minneapolis Coaxial Cable
▪ Measurements of Orchestral Pitch
▪ The 1000-Cycle Ringer-Oscillator
▪ The Copper Oxide Varistor
▪ Repeaters for the C5 Carrier System
▪ Gopher-Protected Cables
Vol. 19, No. 61941-02-011.39 MB▪ Batteries in the Telephone Plant
▪ Dust-Storm Static
▪ The 2B Carrier Pilot Channel
▪ Earth Resistivity Measurements
▪ Power-Factor Correction Equipment for Central Offices
▪ Identifying Cable Wires
Vol. 19, No. 71941-03-011.28 MB▪ A Twin-Channel Single-Sideband Radio Transmitter
▪ Handling DSA Traffic at Toll Boards
▪ 451A-1 Radio Transmitter
▪ Autotransformer for Emergency Repair of Open-Wire Carrier Circuits
▪ Polarential Telegraph Operation
▪ Visual Ringing Signal
▪ Noise from Shunt Capacitors on Power Systems
▪ An Answering-Time Recorder
Vol. 19, No. 81941-04-011.74 MB▪ Remote Control for Reversible Program Circuits
▪ Detecting Faults While Laying Buried Telephone Wire
▪ Locating Hits on Telegraph Circuits
▪ National Defense and the Bell System
▪ "No-Such-Number" Tone for Dial Systems
▪ Studying the Performance of Toll Circuits
Vol. 19, No. 91941-05-011.51 MB▪ Step-by-Step Intertoll Dialing
▪ Aerial Cable Lashing Machine
▪ Lashed Aerial Cable
▪ Measuring System for Carrier Circuits
▪ Measurement of Dynamic Characteristics of Vacuum Tubes
▪ Circuit-Riding the Coaxial Cable
▪ Directional Selection for Toll-Line Signaling
▪ Internal Electro-Analysis
Vol. 19, No. 101941-06-011.40 MB▪ Film Scanner for Testing Television Transmission
▪ Ten-Frequency Airplane Radio Equipment
▪ Ten-Frequency Transmitter
▪ Ten-Frequency Receiver
▪ Wet Strength Tester for Paper
▪ Dielectric Strength Tests on Aerial Cable
▪ Conical Mandrel for Testing Organic Finishes
▪ The 355A Community Dial Office
▪ New Dial-Testing Machine
▪ Adjustable Filters for the 2B Pilot Channel
Vol. 19, No. 111941-07-011.46 MB▪ A Test Set for Pulse Repeaters
▪ Temperature Stability of the 2B Pilot Channel
▪ Electronic Inverter for Interim Power Supply
▪ Sound-Integrating Machine
▪ Telephone Systems Drawings
▪ Bell Laboratories Lecture Equipment
▪ Transmission Talk
▪ Secretarial Key Equipment Using Neon Signals
Vol. 19, No. 121941-08-011.54 MB▪ Radio Telephone Service in Chesapeake Bay
▪ Radio Equipment for the Crisfield Project
▪ Peak Voltages in Carrier Telegraphy
▪ Order-Disorder Transformations in Alloy Crystals
▪ Insulating Paper
▪ The Measurement of Modulation in Carrier Amplifiers
▪ Teletypewriter Oiler
▪ Extended Use of Rubber Insulation in Telephone Cords
Vol. 20, No. 11941-09-012.29 MB▪ The Mirrophone
▪ Facilities for Handling Large PBX Trunk Groups
▪ Conservation of Defense Materials in the Bell System
▪ Observational Standards
▪ Transcontinental Cable One-Fourth Completed
▪ Stock Records and Control
▪ V1 Telephone Repeater Arrangements
▪ Designing the V1 Repeater and Associated Equipment
Vol. 20, No. 21941-10-012.43 MB▪ Automatic Circuit for Determining Load Characteristics
▪ New Coin Collector With Handset
▪ Test for Corrosion of Painted Iron
▪ D-C Substitution Method of Measuring High-Frequency Attenuation
▪ Decentralized Filters for Central-Office Battery Supply
▪ Magnetostriction in Permalloy
▪ "Thru" Selector for Dial Toll Calls
▪ Torque on Silicon Iron Crystal in a Magnetic Field
▪ Crossbar Central B Board
Vol. 20, No. 31941-11-012.43 MB▪ Azimuth Indicator for Flying Fields
▪ Automatic Measurement of Crosstalk at Carrier Frequencies
▪ Environmental Factor in Corrosion
▪ Carrier Systems Help Defense Program
▪ 100-Megacycle Cathode-Ray Oscilloscope
▪ Rhombic Antenna Design
▪ Improvements in 755A P.B.X.
▪ Effect of Mounting-Plate Vibration on Relay Operation
▪ Rubber Handset for Linemen
▪ Dial for New Repairman's Test Set
▪ Switching Devices for Toll System Maintenance
Vol. 20, No. 41941-12-012.69 MB▪ Telephone Network Aids Air Raid Interceptors
▪ Improved Method of Splicing Rubber-Insulated Wire
▪ A Ten-Megacycle Oscilloscope
▪ The Bell System's Biggest Job
▪ Terminal Equipment for the L1 Carrier System
▪ Varistors as Modulators
▪ Station Keys for Telephones
▪ Routes of Broad-Band Carrier Systems
Vol. 20, No. 51942-01-012.91 MB▪ 160-Trunk Incoming Frames
▪ Loading Coils With Cores of Molybdenum Permalloy
▪ Cellulose Acetate Yarn Replaces Silk for Wire Insulation
▪ Stevens Point and Minneapolis Linked by Coaxial System
▪ An Improved Capacitance Bridge for Precision Measurements
▪ Abrasion Test for Finishes
Vol. 20, No. 61942-02-012.54 MB▪ Program Switching and Pre-Selection
▪ Mobilization of Science for the War Effort
▪ Generator for Dial and Busy Tones
▪ War-Time Activities of the Laboratories
▪ Preparation for Air Raids
▪ Highlights in the Bell System During 1941
▪ Crystallinity in Cellulose Esters
▪ Temporary Protection for Cable Splices
▪ Lodgepole Pine Poles
Vol. 20, No. 71942-03-012.34 MB▪ Measuring Small Relative Motions in Central-Office Switches
▪ Brittle Temperature of Rubber
▪ A Telephone Set for Exposed Locations
▪ High-Precision Frequency Comparisons
▪ Grounding of High-Gain High-Frequency Amplifiers
Vol. 20, No. 81942-04-012.14 MB▪ Behavior of Sulfur in Rubber
▪ Developments of the DSA Board
▪ Air-Raid Signal Demonstrated
▪ New Exchange Area Cable
▪ The C2 Control Terminal for Radio Telephone Circuits
▪ Typing Reperforator
Vol. 20, No. 91942-05-012.30 MB▪ Applications of Junction Line Filters
▪ The Junction Line Filter
▪ Small Ringer for Combined Subscriber's Set
▪ Printing Oscillator Scales
▪ A Circuit Continuity Test for the Crossbar System
Vol. 20, No. 101942-06-012.15 MB▪ Transoceanic Telephone Cables
▪ Magnetic Fluxmeter
▪ Lead Calcium Test Castings
▪ Portable Teletypewriter Equipment for Army
▪ The World's Telephones
▪ Factors Controlling Man-Made Radio Interference
▪ Suppressing High-Frequency Disturbances from Telephone Apparatus
▪ A Pilot-Channel Regulator for the K-1 Carrier System
Vol. 20, No. 111942-07-012.57 MB▪ Determining Color in Telephone Cable
▪ Automatic Production of Oscillator Scales
▪ Repeater for Submarine Telephone Cable
▪ Using Less Tin in Cable Joining
▪ Thickness of Aluminum Oxide Coatings
▪ A Grounded-Plate Amplifier for the F-M Transmitter
Vol. 20, No. 121942-08-012.94 MB▪ A Crossbar Tandem Office
▪ Impregnating Varnishes
▪ New Siren Has Successful Trial in New York City
▪ Baskey-Weave Telephone Cords
▪ Rubber Economy in Typewriter Cylinders
▪ Radiation Pattern of the Human Voice
Vol. 21, No. 11942-09-011.50 MB▪ Bell Laboratories and the War
▪ Partition Flexibility at Murray Hill
▪ Abrasion Test for Textiles
▪ Quality Control in Ordnance Inspection
▪ Handling Night Calls at a Dial PBX
Vol. 21, No. 21942-10-012.72 MB▪ Army-Navy Production Award Presented to the Laboratories
▪ The Job Is to Win
▪ A New Telephone Set for the Hard of Hearing
▪ 3A Code-Call Circuit
▪ A Simplified Tear Test
pp. 48-49 missing
Vol. 21, No. 31942-11-012.27 MB▪ Greensalt Preservative for Telephone Poles
▪ A Spread-Scale Recorder
▪ Salvaging for Victory
▪ New Reference Frequency Equipment
▪ Central DSA Switchboard
pp. 82-83 missing
Vol. 21, No. 41942-12-013.54 MB▪ Waiting for Lightning
▪ No. 7 Information Desk
▪ Sequence Switch Cam
▪ A Bridging Filter for Open-Wire Lines
▪ A New Frequency Divider for Obtaining Reference Frequencies
▪ Drafting Full Speed Ahead
▪ Solubility of Metals in Mercury
Vol. 21, No. 51943-01-012.73 MB▪ Stretching Toll Facilities for the Emergency
▪ Outdoor Telephone Booth
▪ Cable Splices and the Hostess Problem
▪ Greensalt Treatment of Poles
▪ Proving-in a Paper Micrometer
▪ Paper Condensers of the Bell System
▪ Radio-Frequency Voltmeter
pp. 118-119 missing
Vol. 21, No. 61943-02-012.40 MB▪ A Super PBX for War Service
▪ School for War Training
▪ Acid Neutralization in Insulating Papers
▪ Rural Telephone Service Using Carrier on Power Lines
▪ Alarm and Comparison Circuits for Reference Frequency Equipment
pp. 140-141, 165-166 missing
Vol. 21, No. 71943-03-012.41 MB▪ The Signal Corps and the Laboratories
▪ Coastal Radio Telephone Systems
▪ Speeding Communication for the Alcan Highway
▪ Ultra-High Frequencies
pp. 180-181, 204-205, 224-225 missing
Vol. 21, No. 81943-04-012.79 MB▪ Rubber Research Laboratory at Murray Hill
▪ Trigger Action from Secondary Electrons
▪ Using High Crystal Harmonics for Oscillator Control
▪ Testing and Rating Air Filters
pp. 248-249 missing