How Telephones work

1
How Telephones work

• By Emma, Bradley, Tiffany and Sean

2
Introduction

• On March 10, 1876, in Boston, Massachusetts,
  Alexander Graham Bell invented the telephone.
  Thomas Watson made the phone itself a crude
  thing made of a wooden stand, a funnel, a cup of
  acid, and some copper wire. But these simple
  parts and the equally simple first telephone call
  -- "Mr. Watson, come here, I want you!" come
  from a complicated past. Bell filed his
  application just hours before his rival, Elisha
  Gray, filed a patent application too.

3

• Bell didnt know how to make the first working
  telephone, so he stole ideas from his rival, and
  beat him to it!

4
Information

• You need a switch to connect and disconnect the
  phone from the network. It connects when you lift
  the handset.
• A speaker - This is a little 25p 8-ohm speaker.
• A microphone - In the past, telephone
  microphones have been as simple as carbon
  granules compressed between two thin metal
  plates. Sound waves from your voice squash and
  unsquash the granules, changing the current
  flowing through the microphone.

5
The End

• We hope you have enjoyed the slide show!