How to Buy a Portable TV

Tricky to Buy: Portable TVs

Using a portable digital TV is a very different experience than using an analog portable TV. Because of the differences in the technology, coverage areas are sometimes very different and certain activities, such as watching TV in the backseat of a car, are more difficult -- if not impossible. Mobile DTV, a new technology that minimizes some of those problems -- particularly the challenge of watching digital TV when on the move -- is being introduced. It's only available in a few areas, however, and it can be viewed only on a few portable TVs. More content -- including the possibility of pay content -- is promised, as are more portable TVs and the ability to watch live TV on smartphones and tablets.

Here are some of the things to consider when shopping for a portable LCD TV:

• Make sure you can receive a signal. Digital signals cover a different area than analog ones and are more likely to be blocked by buildings, hills, etc. Because of that, it's a good idea to confirm that you can receive digital TV signals in the places where you plan to use a portable LCD TV.

• Mobile DTV is available in some markets. A list of what channels are on the air right now -- and which ones are slated to be on the air shortly -- is available at the Open Mobile Video Coalition website.

• Using an external antenna will improve reception. Most digital portable TVs include a built-in whip or rod antenna. However, reports indicate that except in very strong signal areas, these won't do the best job of pulling in digital TV stations. Small, indoor antennas can help as they are more powerful than built-in ones and can be repositioned without moving the set. Some portable LCD TVs include a basic external antenna, with others you'll need to buy it separately. The biggest downside to using an external antenna is convenience, especially if you want to use the TV away from home.

• Digital portable TVs don't work well in a moving vehicle. That's because of the more directional nature of digital signals compared to analog. In some cases, spotty reception is possible, but manufacturers, retailers and reviewers caution not to count on it. New, Mobile DTV technology is being rolled out to minimize that shortcoming, but only a few portable digital TVs are compatible with that.

• Many portable LCD TVs use special batteries. In addition, many have sealed batteries that can't be swapped out by owners. That limits the usefulness of portable LCD TVs for on-the-go viewing or in emergency situations. A handful can be run off standard batteries or use replaceable battery packs.

If it's not crucial that you watch live television, bear in mind that you can now buy TV shows and movies online for download -- so you could watch them later on your iPhone or portable media player.