Telephone - Electronic Switching, Networking, Communication

telephone

Table of Contents

Introduction & Top Questions
The telephone instrument
- Working components of the telephone
  - Power source
  - Switch hook
  - Dialer
  - Ringer
  - Transmitter
  - Receiver
  - Anti-sidetone circuit
- Development of the telephone instrument
  - Early sound transmitters
  - Gray and Bell: the transmission of speech
    - The first devices
    - The search for a successful transmitter
  - Development of the modern instrument
- Cordless telephones
- Personal communication systems
The telephone network
- Switching
  - Switching systems
    - Manual switching
    - Electromechanical switching
    - Electronic switching
    - Digital switching
  - The switching network
- Signaling
  - Call-number dialing
    - Rotary dialing
    - Push-button dialing
  - Interoffice signaling
    - In-band signaling
    - Out-of-band signaling
- Transmission
  - Development of long-distance transmission
    - From single-wire to two-wire circuits
    - Problems of interference and attenuation
    - From analog to digital transmission
    - Coaxial cable
    - Microwave link
    - Optical-fibre cable
  - Overseas transmission
    - Terrestrial radio
    - Undersea cable
    - Satellite

References & Edit History Quick Facts & Related Topics

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As telephone traffic continued to grow through the years, it was realized that large numbers of common control circuits would be required to switch this traffic and that switches of larger capacity would have to be created to handle it. Plans to provide new services via the telephone network also created a demand for innovative switch designs. With the advent of the transistor in 1947 and with subsequent advances in memory devices as well as other electronic devices and switches, it became possible to design a telephone switch that was based fundamentally on electronic components rather than on electromechanical switches. ...(100 of 8665 words)

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