Common-Battery

PARTY-LINE SYSTEMS _By K. B. Miller and S. G. McMeen_

Non-Selective Party-Line Systems--Series and Bridging--Signal
Code--Selective Party-Line Systems: Polarity, Harmonic, Step-by-Step,
and Broken-Line--Lock-Out Party-Line Systems: Poole, Step-by-Step, and
Broken-Line

PROTECTION _By K. B. Miller and S. G. McMeen_

Electrical Hazards--High Potentials--Air-Gap Arrester--Discharge
across Gaps--Types of Arrester--Vacuum Arrester--Strong
Currents--Fuses--Sneak Currents--Line Protection--Central-Office and
Subscribers' Station Protectors--City Exchange
Requirements--Electrolysis

MANUAL SWITCHBOARDS _By K. B. Miller and S. G. McMeen_

The Telephone Exchange--Subscribers', Trunk, and Toll
Lines--Districts--Switchboards--Simple Magneto
Switchboard--Operation--Commercial Types of Drops and Jacks--Manual
vs. Automatic Restoration--Switchboard Plugs and Cords--Ringing and
Listening Keys--Operator's Telephone Equipment--Circuits of Complete
Switchboard--Night-Alarm Circuits--Grounded and Metallic Circuit
Line--Cord Circuit--Switchboard Assembly

REVIEW QUESTIONS

INDEX