Over-the-Air (OTA) television broadcasts offer a free alternative to cable and satellite services. The broadcasts, available in digital form since June 2009, include local news, popular entertainment and movies -- in all, a large number of channels available to anyone in or near most cities. To receive these broadcasts, you need the right kind of antenna and channel tuner; the exact type depends on the kind of television you own.
To receive the maximum number of available digital TV broadcasts, you need a digital antenna capable of receiving both VHF and UHF transmissions. A simple indoor antenna is sufficient if you live within about 10 miles of the transmitter tower, where the signal is strong. Farther out, an amplified antenna may be necessary to pull in moderate signals. From 30 to 60 miles, you'll need an outdoor antenna on a rooftop mast or tower. Depending on the height of the transmitter tower, the signal becomes very weak beyond 60 miles and the curvature of the earth interferes with clear reception.
Signal Splitter or Amplifier
One antenna can usually provide an adequate signal for one or two TV sets. If you have two televisions, you connect a device called a splitter to the cable coming from the antenna; the splitter provides two outputs, so one TV connects to each output with the same type of cable. For three or more TVs, a distribution amplifier actively boosts the signal, providing clear picture and sound to each of several outputs. An amplifier runs on standard AC power, so it must be located near an outlet.
If you have a television made before 2005, chances are it has a tuner designed to receive analog broadcasts which, by law, are no longer transmitted in the US. You can, however, buy a converter box that converts a digital signal to an analog one, letting you watch the latest broadcasts on an older TV set, although it won't have high-definition video like a more recent model. The converter box has its own tuner built in, so you change channels from the box but not with the TV's tuner.
Wide-screen TVs sold in the US since 2005 have a tuner built in that handles digital signals. If you own a TV that was made recently, the set can work with the signal from a digital antenna directly; you don't need a separate converter box. This means you can change channels using the TV's remote.
The simplest setup for over-the-air TV broadcasts connects a cable between an indoor tabletop antenna and a digital TV set using the TV's antenna input. For recording shows, you can connect the antenna to a DVR input and send the DVR's output to the TV. If you have a digital TV and an older analog set, you connect a cable between the splitter and the antenna, a second cable from the spitter's output to the digital TV, and a third cable from the splitter's other output to a digital converter box. A fourth cable carries the analog signal from the converter box to the analog TV's antenna input.
- FCC: Digital Television
- FCC: Antennas and Digital Television
- Northeastern University: Antennas & Propagation
- Channelmaster: How Much Signal Do I Lose Going through a Splitter?
- Consumer Reports: How to Survive The Digital TV Transition
- WTTW: Digital Countdown
- Ready To Cut The Cable TV Cord? Here's How To Do It