A transmitter not only transmits one channels audio or video signal, but in most cases many different channels.
Receiver (TV set)
A receiver is usually integrated in your TV set and this receiver is able to grab radio waves (the transmitted signal) and process these radio waves back to audio and video electric signals that can now be played on your TV set.
Display Device
A display device is usually a TV set, but can also be just a monitor. The display device is able to receive electrical signals (usually sent from the receiver) and turn these electrical signals to a viewable image. Most standard TV sets incorporate a cathode ray tube (CRT), however new display devices can include LCD (liquid crystal display) and Plasma (gas charged display) display devices among others.
Sound Device
While most sound devices are built into your TV set in the form of speakers. Audio signals are obviously needed to match up with the video being shown to the viewer. Many newer TV sets have outputs to send the TV sound to high quality speakers that reproduce sound much better. Since audio signals can include surround sound technology, the TV set is able to send audio signals to the proper speakers located around your room.
Three Major Ways to Receive TV Signals
There are three major ways to receive television broadcasts. They include Broadcast TV, Cable TV and Satellite TV.
Broadcast Television
Broadcast TV is usually defined as TV signals which are transmitted from a terrestrial source, usually a transmission tower. Most broadcast TV signals are free to anyone with a receiver to pick them up. They include traditional TV channels that broadcast standard TV signals on specific radio frequencies.
Television signals are transmitted on a range of radio frequencies (RF) that includes Bands III, IV and V.
The FCC (Federal Communications Commission) has allocated 6 MHz of bandwidth for each TV channel. Each TV channels is on one of 3 bands ranging from Bands III, IV or V. Here is the breakdown:
Band III
Channels 2 to 6 (54 to 88 MHz) Band IV
Channels 7 to 13 (174-216 MHz) Band V 
Channels 14 to 83 (470 to 890 MHz)
VHF (Very High Frequencies) are channels that include channels 2 to 13. UHF (Ultra High Frequencies) are channels that usually include channels 14 to 83.
The Reason for using these Bands is that these radio frequencies are great for carrying TV signals (both audio and video signals). These bands provide high quality audio and video with reatively low interference. These radio waves have a long range and can penetrate structures such as walls and building exteriors.
Satellite TV
Satellite TV uses a different form of transmission. Instead of transmitting signals from the ground, satellite TV transmits from satellites orbiting the earth. Satellite sig-
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