The outside of this portable radio has the tuner at the right and the speaker at left. The antenna can be seen at the upper right of the radio.		Knobs over the metal pins seen here are attached to the internal parts of the radio. These knobs adjust the tuner (station) and volume		The speaker is seen at left.

• Transmitter - takes message (ex. voice), encodes a sine wave from message, and transmits it with radio waves
• Receiver - receives and reproduces signals transmitted in the air
• Antenna - wire, set of wires, or metal stick used to send out or receive electromagnetic waves
• Tuner - separates one sine wave from another, and amplifies a particular frequency (while ignoring other frequencies in the air)
• Speaker - amplifies the sound

Baby Monitor - a simple, mini-radio with a transmitter and receiver		Cell Phone - contains both a transmitter and receiver that operate at the same time		Portable Radio -will work with batteries or AC from an outlet

ELECTRICITY

A radio transmitter sends signals through the air in the form of a radio wave. The radio itself uses electricity from an electric cord or batteries and turns on the radio. The antenna seeks the radio waves that are flowing through the air. When the information of the waves are found, they are transferred into sound waves through the speakers of the radio. Then the speakers vibrate the sound waves and then the sound waves are heard by your ears.