How to Split HDTV Antenna Signals

by David Lipscomb

Modern high-definition TV feeds don't necessarily require new hardware to keep TV distributed in your home, but if you're starting fresh there are a few key things to consider. Keeping the signal strong from the antenna to each set in your house is the result of proper cable termination techniques and using the right equipment to maintain consistent and reliable reception.

Boosting the Feed

Any longer coaxial cable run in excess of 200 feet from the antenna to the splitter normally requires a preamplifier. This device is mounted at the antenna mast, providing a boost to the signal as it leaves the array and enters the structure. Preamplifiers are a necessary component in any amplified television distribution network, providing the downstream amplifier with sufficient signal strength. Preamps are also required if you happen to be located at the broadcast fringe, typically between 75 to 100 miles from broadcast towers, or if you're in a valley or surrounded by buildings or trees.

Cable Considerations

RG-6 coaxial cable is the preferred interconnect for getting HDTV signals from your antenna to your TVs. RG-6 features multiple layers of shielding, rejecting harmful radio frequency and electromagnetic interference from reducing signal strength. If you're making your own cable, proper termination techniques must be used to maintain proper signal strength and maintain the longevity of the cable itself. Coaxial strippers take off about 1 inch of outer insulation, without chewing up the inner braided shield. Once this is gone, you fold back that inch of shielding, then slide the new coaxial connector over the exposed center conductor and the white plastic that surrounds it. Coaxial crimpers lock the connector in place. Other specialized options include snap-lock connectors and tools, recommended for increased moisture rejection and more robust connector hardware.

Splitter Options

If you're feeding several TVs in the house, there's no compelling need to use more than a decent non-amplified splitter in your basement or attic. However, more than four splits dictates the use of an amplified splitter. Each split results in a 3 decibel loss relative to the signal strength from the antenna. This is cumulative, so the last split in the chain might be heavily downgraded to the point where the tuner cannot "see" the feed -- especially as the total run begins to approach 200 or more feet. Amplified options boost each split, maintaining proper signal strength across the array. Others offer the ability for you to make individual gain adjustments, dialing in and out to boost as needed. Each outgoing cable simply screws to their relative terminals, with the incoming feed screwed to its terminal as with any other splitter. Amplified devices require AC power.

No Grey Area

A benefit to HDTV signals is also a potential drawback when it comes to splitting feeds. As with any digital broadcast or transmission, if the signal is present you'll see a perfect image. At a certain point below that threshold, you don't see anything -- or a pixelated jumbled mess. This means that unless the proper signal strength is maintained, you won't see anything -- unlike analog broadcasting, you don't have much margin for error. Ensuring each cable in the chain is properly terminated and amplified means that each set in the home that features an ATSC -- or digital -- tuner should receive a maximum-quality signal.

About the Author

David Lipscomb is a professional writer and public relations practitioner. Lipscomb brings more than a decade of experience in the consumer electronics and advertising industries. Lipscomb holds a degree in public relations from Webster University.

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