Table of Contents

1. Overview
   1.1 Scope
   1.2 Purpose
2. References
3. Transmitting and receiving equipment
   3.1 Relaying requirements
   3.2 Basic types of audio-tone systems
   3.3 Power supplies
   3.4 Equipment protection from surge phenomena
   3.5 Tone level meter
   3.6 Frequency translation protection
4. Voice grade channels
   4.1 Introduction
   4.2 Need for joint discussions
   4.3 Characteristics of voice grade channels
   4.4 Private networks
5. Application principals
   5.1 Audio-tone relaying systems
   5.2 Mode of operation
   5.3 Signal and channel arrangements
   5.4 Signal transmission
   5.5 Operating time of the system
   5.6 Noise and noise suppression
6. Installation and testing
   6.1 Installation considerations
   6.2 Testing
   6.3 Periodic maintenance
Annex A (informative) Bibliography
Annex B (informative) Example of audio-tone circuit
        considerations
Annex C (informative) Signal level measurements and
        terms

Abstract

Describes use of audio tone communication over telephone channels for power system relaying. Also covers leased and user owned telephone systems. Includes transmitting and receiving equipment, application principles, installation, and testing.

General Product Information

Published
Document Type	Standard
Status	Current
Publisher	Institute of Electrical & Electronics Engineers
Pages
ISBN
Supersedes	IEEE 305 : LATEST