How Does HDTV Work? > Broadcast Signals
HDTV can be received today via three different systems. Today there are dozens of high definition programs transmitted in American homes around the clock.
Broadcast
According to the National Association of Broadcasters, there are currently 1,315 stations in the U.S. transmitting digital TV signals. Many of these stations broadcast high-definition content as well. HDTV is offered by CBS, NBC, Fox, WB, UPN, and PBS stations. All over-the-air content is free. Requires an digital tuner - either built into the TV, or as a separate set-top box.
Cable
Many Cable systems offer premium HD movie channels and regional sports, as well as some local HD broadcast channels. Cable also has its own exclusive network called In HD and In HD 2, providing movies, music and varied programming. Requires a CableCARD or cable digital HD set-top box.
Satellite
The satellite companies are continually expanding their HD offerings to movies on HBO, Cinemax, Showtime, The Movie Channel, Starz, HD Net Movies and Encore. Arts, Music, Animation, Extreme Sports, and Travel Logs are now available full-time in HD via satellite. Requires special satellite HD receiver. Availability of local HD broadcast channels varies by market and satellite provider.
