Digitaltvreviews.net is a collection of information about new television technologies which harness the power of digital television.

Our main focus is on reviews and here you can find out which televisions are outstanding value and which models are lemons.

You can also compare LCD and Plasma screens and read recent digital TV news from around the world. Enjoy!

 

What is Digital Television?

Digital television (DTV) uses digital modulation and compression to broadcast video, audio and data signals to television sets.

DTV can be used to carry more channels in the same amount of bandwidth than analog TV (6 MHz or 7 MHz in Europe) and to receive high-definition programming. The digital signal eliminates common analog broadcasting artifacts such as "ghosting", "snow", and static noises in audio. However, when the signal is transmitted at a too low data rate DTV replaces these artifacts with new MPEG compression artifacts, such as "blocking", and may fail to work entirely in situations where analog television would have produced an impaired but watchable picture. Depending on the sophistication and level of the error correction defined by the technical standard that the broadcaster complies with, DTV may either work perfectly or not work at all.

The switch-over to a DTV signal often coincides with a change in picture format from an aspect ratio of 4:3 to one of 16:9. This enables TV to get closer to the aspect ratio of movies and human vision. On traditional screens this leads to "letterbox" black bars above and below the picture due to placing the 16:9 picture in a 4:3 frame. The previous aspect ratio of 4:3 was chosen to match the Academy of Motion Picture Arts and Sciences standard ratio of the day.

New types of televisions have been developed in recent years which really harness the power of digital television. 'High Definition televisions' which use LCD and Plasma technologies allow viewers to watch digital television broadcasts in their full glory.

Analog switch-off

In general, viewers who are happy with their existing analog TV systems tend not to adopt terrestrial DTV systems (so-called "digital refuseniks").

There are also a significant number of DVB or free-to-air satellite viewers who retain analog terrestrial capability solely for news, sport, or other purely local broadcasts. The cost of a second digital set-top box for each TV just for a few local channels may be difficult to justify if these households already watch digital signals on most channels and have capital tied up in DVB-S or proprietary dish hardware.

In the subscription-TV market, many who want cable-TV-like services buy either cable TV (where available) or satellite DTV.

As such, those most able to afford terrestrial DTV equipment are the ones abandoning "over-the-air" reception for satellite or other signal sources that provide a wider selection of programming.

Governments are responding to this with an attempt to force the issue by enforcing planned "switch-off" dates for analog television, but are encountering resistance from the public, as they fear that this will mean that they will need to replace every television they own, including portable TVs and bedroom TVs, or buy additional digital receivers (a set-top box).

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