How To Select a Digital HDTV Antennaby David Lipscomb
Knowing that the best-looking high-definition broadcasts are free from local broadcasters is enticing. However, you have to choose the right antenna for your location, mounting height and whether or not you're forced to deploy an antenna inside. AntennaWeb is a consumer-information website cosponsored by the Consumer Electronics Association and the National Association of Broadcasters, devoted to helping you choose the right antenna for your situation using a standardized color coding scheme.
Analog, also known as NTSC, broadcasting dominated the airwaves for decades. Although reception and performance was generally very good, analog TV broadcasts also suffered from "ghosting," when the signal faded enough from rain or high winds to cause problems. NTSC signals used VHF elements primarily for most of the channels, with some using UHF. ATSC digital signals are an all-or-nothing proposition; the picture is either good or not there at all, but never degraded. ATSC splits the responsibility between the VHF and UHF elements. Modern antennas have differing focus on VHF and UHF arrays to fit various broadcasting and reception environments, making it all the more important to choose the specific one for your location.
Directional Versus Omnidirectional
Directional antennas offer the best signal strength if your local broadcast towers are clustered together geographically. On a map, if the broadcasters are within a 20 degree radius from one another, more than likely a directional antenna is your best choice. However, you may encounter a scenario where most of the towers are clustered, with one or more important channels away from the rest. To adequately receive all of them, you want an omnidirectional array. Although the overall signal strength is reduced, it's unlikely you'll have significant degradation unless one of those towers is more than 50 miles away, considered a fringe distance by broadcasting standards.
Indoor and Outdoor Antennas
Homeowner associations by law cannot prevent you from installing an outdoor antenna, but that's no guarantee that an antenna installed outdoors will look nice or perform well. If you live within 20 miles of most local broadcast towers, a powered indoor antenna might be your best choice. Although they're generally less powerful, they're less obtrusive visually. If you're in an area with good signal strength, a sleek indoor or outdoor square "pizza box" unit may serve your needs well. These devices are generally amplified to make up for the smaller surface area of the internal elements. You should place these devices close to windows or sliding glass doors to minimize interference from brick, stucco and other signal-blocking materials.
If your antenna is mounted 50 miles or more from local broadcasters or the coaxial cable from the antenna to your tuner, amplification is a good idea. Preamplifiers mounted on the mast of the antenna near the elements boost whatever signal is present, while powerfully driving that signal down the coaxial cable. An amplifier at the other end receives and boosts the feed, presenting each tuner in the structure with the strongest possible signal. Amplifiers are also useful in cases where multiple splits to a few tuners or televisions are needed. Each split drops 3 decibels of signal, counteracted by the presence of an amplifier.
CEA Color Coding
After you enter your address and mounting height into the form at AntennaWeb, you are presented with one or more color-coded antenna options. Matching your color to the corresponding color on retail packaging makes the antenna selection process a little easier. However, pointing the unit correctly while avoiding multipath signal bounce from trees and other structures is still an important element. In most cases, mounting an antenna as high as possible and away from obstructions, metal siding and power lines counters most of the problems you'll encounter.
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