What Converts sound to a signal in a telephone

The part you talk into, that converts the sound of your voice

into an electrical signal, is a tiny microphone.

- - The sound waves from your voice are ripples in the air.

- - In most microphones, there's a tiny coil of wire hanging

between the ends of a tiny magnet.

- - When the ripples in the air hit the little coil of wire, they

make it vibrate (wiggle) slightly.

- - When a coil of wire wiggles in the field of a magnet,

a current flows in the wire.

There's your electrical signal!