• Home

• Preface

• Alexander Graham Bell

• Telecommunications history

• How the telephone works

• Phone FUN facts

• Why the Phone Works When the Lights GO OUT

• FTTP (Fiber to the Prem)

• Future of Telecommunications

• Crossword Puzzle

• Word Search

• Glossary

• Credits

• Speech by Thomas Watson

How the telephone works

• If the called line is not busy, the Telephone Company computer places a ringing signal on the called line. This signal will make the phone ring and will alert the called person that someone is calling them.

• The caller also hears the ringing signal placed on the line. This alerts the caller that the call is going through.

• When the called person picks up the phone to talk, the Telephone Company computer senses this, and removes the ringing signal thereby preparing the line for use.

• When the called person says “Hello,” the transmitter (mouthpiece) in their phone acoustically vibrates. That acoustic vibration changes into a varying electrical signal on the wires between the two phones. The changing electrical signal on the telephone line is converted by the far end receiver (earpiece) back into acoustical vibrations and into the spoken word “Hello.”