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You may not realize it, but you use
the radio every single day even if you don't take a trip in
the car. Some examples are garage door openers, radio controlled
toys, cell phones, television, wireless clocks, police radios,
GPS receivers, and satellite communications devices. The radio
has two parts, the transmitter and the receiver. The transmitter
takes a message and encodes it onto a sine wave, and transmits
it with radio waves. The receiver receives the radio waves and
decodes the message from the radio sine wave. |
You can get an idea of how a radio transmitter works with a battery
and a piece of wire. A wire sends electricity through the wire if
you connect the wire between the two ends of the battery. The electricity
creates a magnetic field around the wire strong enough to affect
a compass. In a radio transmitter, the same thing occurs.It converts
a sine wave from the transmitter into a magnetic wave that a receiver
can pick up.
Another important part of a radio is the antenna. An antenna puts
radio waves into space and a receiver picks up as much of it as
it can and supplies it to the tuner. The radio is a very influential
invention that has changed the worlds of communication and entertainment.
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