Reception Information | About the Station | CW33 Dallas/Fort Worth

Reception Information

The following information is intended to give you an overview of UHF television reception and help in improving the reception of KDAF-TV, CW33 or KDAF digital 32.

Introduction:
The purpose of this Guide is to provide information for improving UHF television reception in the home. In the Dallas/ Fort Worth area, there are 43 broadcast television stations on the air. 6 VHF stations, 19 UHF analog stations, 1 VHF digital station and 17 UHF digital stations. The majority of the stations are located in Cedar Hill Texas. The KDAF transmitter facility, once located on the west side of highway 67, is now on the east side of highway 67. With this change, depending on the location of your home or receive point, some adjustments may have to be made to your antenna system to ensure a good signal reception. This adjustment may or may not affect your reception of the other stations in our area. A second UHF antenna may be required to satisfy both the KDAF and other station reception criteria. Typically, clear UHF reception for either analog or digital signals requires a bit more attention to antenna installation than does standard VHF reception. This can be accomplished with minimal cost and will ensure reliable reception of KDAF and all other Dallas Fort Worth UHF television stations. Improving UHF reception can be a do-it-yourself job. Even if the work is given to a professional, the information in this guide will provide a better understanding of what is needed and what can be expected.

Poor Reception And Poor Antennas:
If UHF reception in general is bad, how it's bad can help determine the problem. "Snow" is visual noise caused by a weak signal, poor antenna system, the set itself, or a combination of these. "Ghosts" or multiple images are caused by a signal arriving from two or more directions simultaneously reflected off buildings, trees and mountains. In the digital realm, you will either have a good picture or no pictures at all. A good antenna system often solves these reception problems. An outdoor antenna is better than an indoor antenna and a necessity for receiving digital broadcast signals. An indoor antenna is better than no antenna at all. If an outdoor antenna is needed for VHF, you'll almost certainly need an outdoor antenna for UHF. But if good VHF reception can be obtained with and indoor antenna, a loop or other UHF antenna on the set may also work for analog television reception.

Indoor Antennas:
All indoor antennas can be adversely affected by the walls of a house, inadequate height, and by movement of people in the room. Loop or single bow tie UHF antennas are usually not satisfactory. They are difficult to adjust for maximum signal pick up or for elimination of ghosts. Be sure their lugs are secure to the UHF antenna terminals on the back of the set or the balun that connects to your set. The indoor combination VHF/UHF antenna has a multi-position switch to get the best picture. Some examples of indoor set top antennas are displayed here. Unfortunately, indoor antennas have proven to be somewhat inadequate in the reception of digital broadcast signals. It is highly recommended that an outdoor antenna system be employed for digital television reception.

Outdoor Antennas:
There are many different kinds of outdoor antennas available in a wide price range. The kind selected is determined primarily by the geographic location of the receiver. Television signals are strongest when the station transmitting tower and the home receiving antenna are in line-of-sight. If the line-of-sight is blocked or weakened by mountains, buildings or trees, the signal, likewise will be weakened or lost. The signal will also grow weaker as it travels farther. "Gain" is the measure of an antenna's sensitivity-- and its ability to pick up signals. It is measured in decibels (dB). The farther away from the station tower, the more gain the antenna should have. Gain can also vary from channel to channel. For example, an antenna's advertised gain rating may be at Channel 20, but the gain may be much less at Channel 50. Make sure the dealer guarantees that the antenna purchased is for channels in your area. Where buildings or other obstructions cause "ghosts," an antenna with good directivity is recommended. Directivity is the ability to receive only those signals at which an antenna is pointed. Highly directive antennas have narrow receiving angles (measured to degrees) and high "front to back ratios." To insure the best reception aim the antenna carefully. An example of a typical VHF/UHF antenna is displayed to the right.

If a good VHF antenna installation is already on hand, it will probably be less expensive to add a good quality UHF antenna on the same mounting mast, The separate UHF antenna also will permit pointing to VHF and UHF antennas independently. If all television signals are coming from the same direction, both VHF and UHF reception can be improved. Choose an antenna according to the distance to the most distant UHF station for which reception is desired. However, the most expensive and longest-range antenna may limit your reception of multiple sites, as is the case in the DFW area. There are several good combination VHF/UHF antennas available and many outlets that one can purchase one.

If the UHF stations to be received are located in different directions from your house, which can be the case in the DFW area, a second UHF antenna can be installed and combined to a single cable. It is also possible to attach the antenna system on a device, known as a rotor that allows you to move the aiming of the antenna assembly.

Lead-in Lines:
A good lead-in line installation delivers the signal from antenna to set with relatively little loss of strength. Quality in this choice in an important factor for reliable reception. Flat ribbon twin lead, (pictured below) was the standard for many years. This type of line does not work well for UHF. Lead-in lines deteriorate over time. Lead-in lines over five years old (or less depending on environmental conditions) should be replaced with new cables. It must be noted that the flat lead-in lines do not work well with digital television signals.

Coaxial cable may cost more initially, but less frequent replacement makes it less costly over time. Typically this type of cable will need a matching transformer (balun) at the antenna and possibly at the set if it is an older model. All new TV sets come with a single connector known as an "F" connector. Most combination VHF/UHF antennas have a connection for a single lead-in line, and in most locations a single high quality lead-in line will deliver good VHF and UHF signals. With separate VHF and UHF antennas, the separate cables will need to be tied together using a splitter/combiner.

Splitters (also called "combiners") will have the effect of reducing the signal strength. In a weak signal area you may need to add an amplifier to the antenna. If an amplifier is added, it should be in the line as close to the antenna as practical.

Installation - The Best Antenna Location:
Higher is usually better. Six to eight feet above the roof should be adequate. Attic installations do work but the metal flashing in the roof will reduce the signal strength. Buildings or other obstructions shouldn't block the line-of-sight to the TV tower. The shorter the lead-in line, the less signal is lost. Avoid attaching the antenna to a working chimney. Fumes are harmful to the aluminum antenna parts. Heed local ordinance.

Tips On Installation:
Your dealer can advise what hardware to use to mount the antenna. Be sure the antenna is assembled correctly. Read the instruction sheet carefully. Check the area to be sure there are no power lines nearby that could touch the antenna, lead-in lines, or metal extension ladder. Ground the antenna mast electrically, using No. 6 or larger wire and standard ground rod to help protect the antenna and TV set from lightning. Masts taller than 10 feet need guy wires. Aim the antenna(s) in the direction of the TV station towers. This will be Cedar Hill Texas. Where this is not feasible, a signal reflected from a large building or other obstruction may work. Experiment with antenna height and aiming, because a few inches can make a big difference. Have someone watch the set and report of reception quality as the antenna position is changed. Keep lead-in line free of splices and sharp bends. Form the lead-in line into a half loop where it enters the house, so rainwater will drip off. Seal the entry with a waterproof material. Excess line coiled in the wall or behind the set can cause signal loss and interference.

Multiple Sets:
More than one television set may be connected to one antenna by using a multiple set "splitter or combiner." Most splitters weaken signals. If signals are weak a splitter and an amplifier or distribution amplifier may be needed.

Cable / Satellite Services:
Cable systems rarely carry a UHF station on its own UHF channel. UHF stations are usually transmitted either on an unused VHF channel or on one of the special cable channels available through a set-top converter furnished to the subscriber. The cable company will provide a listing of channels to which the UHF channels have been converted. On newer television sets, the setup menus allow for either off air reception or cable reception. Make sure that you chose the appropriate setting for your situation. KDAF-TV, CW33 is now available on both DirecTV and Dish satellite services. There is an additional charge for access to the local channels. If you have satellite service and chose not to subscribe to the local channel offerings, you will still need an alternate method of receiving KDAF and other UHF channels in our area using either a cable service or an off air reception method.

Digital Television / HDTV:
KDAF began over the air digital broadcast operations on channel 32 in January of 2001. We currently duplicate our NTSC programming on channel 32.

The CW has begun broadcasting selected shows in HD. Please consult our channel listings for dates and times.

It is anticipated that this information will help in resolving many reception issues that exist. If you have a specific question regarding our service please email your question to kdaf_engineering@tribune.com.