Chapter 11
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Connecting Over-the-Air Antenna
Transmit Channel Numbers
For information on channel numbers, you can visit the National Association of Broadcasters (NAB)
web page at www.nab.org. On this web page, go to www.nab.org/Newsroom/Issues/digitaltv/
DTVstations.asp for a listing of digital broadcast stations and their Transmit Channel numbers.
Note: Where Transmit Channel is displayed by the 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 Over-the-Air TV Broadcasts
Over-the-air 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
antenna instead of the 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. New digital over-the-air
TV signals are broadcast and received in the same way. Digital over-the-air TV broadcasting uses
advanced technology like that of the DISH Network to deliver superb picture quality and CD quality
sound. However, digital over-the-air signal reception (like analog over-the-air signal reception)
depends on several things:
•The distance between the broadcast station and your home (the farther away the station, the
weaker the signal);
•The broadcast station's power (the lower the power, the weaker the signal);
•Obstacles between the station and your home, such as mountains, buildings, trees, or other
objects (these may block or reflect the signal before it reaches you);
•Multiple broadcast 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 images caused by receiving reflected signals along with the direct signal from a
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 is all black or all blue).
•Digital broadcasts 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.
Chapter 11 Two Color.fm Page 98 Wednesday, August 2, 2006 1:00 PM