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Connecting an Over-the-Air Antenna
Chapter 12
Transmit Channel Numbers
For information on channel numbers, you can visit the National Association of
Broadcasters (NAB) web page at www.nab.org.
For a list of digital local broadcast stations and their Transmit Channel numbers, you can
go to http://www.broadcastpublicservice.org.
Note: Where the term Transmit Channel is displayed by your receiver, the NAB web page
uses the term RF Channel. These terms mean the same thing.
Another good source of local channel information is available from the Consumer
Electronics Association (CEA) web page at: www.antennaweb.org. This website provides
recommendations for antenna types and pointing directions.
About Optional Over-the-Air TV Broadcasts
Over-the-air local TV signals are broadcast from stations on the ground, while satellite TV
signals are broadcast from satellites in space. You receive over-the-air TV signals using
an indoor or outdoor TV antenna instead of a satellite dish. You are likely familiar with
analog over-the-air TV signals—these are the signals that have been used to broadcast
TV for many years. The new, digital over-the-air TV signals are broadcast and received in
much the same way. Digital over-the-air TV broadcasting uses some of the same
advanced technology as DISH uses to deliver superb digital picture quality and CD-quality
sound. However, digital over-the-air signal reception (like analog over-the-air signal
reception in the past) depends on several additional factors:
• The distance between the broadcaster’s transmitting station and your home (the
farther away the transmitter, the weaker the signal).
• The broadcast station's power (the lower the power, the weaker the signal).
• Obstacles between the transmitter and your home, such as mountains, buildings,
trees, or other objects (these may block or reflect the signal before it reaches you).
• Multiple transmitting stations (to receive good signals from several stations, you may
need to compromise in how you aim the antenna or you may need more than one
antenna).
The effects of poor digital reception are different from the effects of poor analog reception:
• Poor analog reception usually causes the TV picture to be “snowy” or to include
“ghosts,” that is, multiple overlapping images caused by receiving reflected signals
along with the direct signal from a broadcast station.
• Poor digital reception may cause the TV picture to be “pixelized,” that is, broken up
into small squares of various colors, or to be lost completely (the TV screen shows all
black or all blue).
• Digital broadcasts can often provide either a very good picture or no picture at all.
• You may be able to receive a poor analog signal, but not be able to receive a digital
signal at all. Or vice versa.
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