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

Images, Videos & Interactives

Alexander Graham Bell and the New York City–Chicago telephone link

How the telephone was invented

Alexander Graham Bell demonstrating the telephone

Evolution of the Phone: A look at telephone technology through the decades.

actor portraying Alexander Graham Bell

telephone c. 2000

telephone: Alexander Graham Bell's sketch of a telephone

Bell, Alexander Graham: telephone

Alexander Graham Bell

For Students

telephone summary

Read Next

A Factory Interior, watercolor, pen and gray ink, graphite, and white goache on wove paper by unknown artist, c. 1871-91; in the Yale Center for British Art. Industrial Revolution England

Inventors and Inventions of the Industrial Revolution

Abstract vector hi speed internet technology background

History of Technology Timeline

Discover

After a perfect launch, spectators try to catch a last glimpse of Space Shuttle Columbia, barely visible at the top end of the twisted column of smoke.

7 Accidents and Disasters in Spaceflight History

Hemp (Cannabis sativa).

9 Mind-Altering Plants

A Factory Interior, watercolor, pen and gray ink, graphite, and white goache on wove paper by unknown artist, c. 1871-91; in the Yale Center for British Art. Industrial Revolution England

Inventors and Inventions of the Industrial Revolution

Aphrodite. Greek mythology. Sculpture. Aphrodite is the Greek goddess of love and beauty.

12 Greek Gods and Goddesses

Statue of Liberty in front of the skyline of Manhattan, New York City, New York.

Who Was the Woman Behind the Statue of Liberty?

Hindu Holi Festival celebrations with colored water, powder and colorful flower petals thrown over celebrants at a Hindu temple in Mathura, Uttar Pradesh, India on March 24, 2021.

Holi: Festival of Colors

Moonrise over Tucson, Arizona

Why Doesn’t Arizona Observe Daylight Saving Time?

telephone: Facts & Related Content

Written and fact-checked by The Information Architects of Encyclopaedia Britannica

Facts

Also Known As	telephony

Photos and Videos

Alexander Graham Bell and the New York City–Chicago telephone link

Alexander Graham Bell demonstrating the telephone

actor portraying Alexander Graham Bell

telephone c. 2000

telephone: Alexander Graham Bell's sketch of a telephone

Bell, Alexander Graham: telephone

Alexander Graham Bell

first commercial telephone

AT&T magneto wall telephone

How the telephone was invented

See All Videos, Images, Audio and Interactives →

Topics

ringer anti-sidetone circuit switch hook mobile telephone E1A handset telephone box local loop videoconferencing videophone local area network Internet television broadcasting radio technology satellite communication telegraph wireless communications broadband technology jamming receiver

Dig Deeper: More Articles That Discuss This Topic

human-factors engineering: Push-button telephone

Key People

Watch a silent short of Thomas Edison, who invented the phonograph and incandescent electric light

Thomas Edison

American inventor

Alexander Graham Bell

Alexander Graham Bell

American inventor

Johann Philipp Reis

German physicist

Watson, Thomas Augustus

Thomas Augustus Watson

American industrialist

Frank Baldwin Jewett

American engineer and executive

Berliner, Emil

Emil Berliner

American inventor

Elisha Gray

Elisha Gray

American inventor

Sir William Henry Preece

British engineer

Pupin, detail of a portrait

Mihajlo Pupin

Serbian American physicist

Harold DeForest Arnold

American physicist

Quiz

ornithopter. Airplane and Aircraft. 3D illustration of Leonardo da Vinci's plans for an ornithopter, a flying machine kept aloft by the beating of its wings; about 1490.

Inventions: From Bayonets to Jet Engines

List

A Factory Interior, watercolor, pen and gray ink, graphite, and white goache on wove paper by unknown artist, c. 1871-91; in the Yale Center for British Art. Industrial Revolution England

Inventors and Inventions of the Industrial Revolution