Preceding digital television (
DTV), all televisions
encoded pictures as an
analog signal by varying signal
voltage and radio frequencies. DTV is fast replacing analog TVs as
digital broadcasting enables broadcasters to offer
television with movie-quality picture and sound.
Analog
systems are more commonly known as NTSC systems.
A U.S. Senate panel has set an April 7, 2009, as the deadline for television
stations to switch entirely from analog to digital broadcasts. Analog
televisions will work until all analog broadcasting ceases. Once the transition
to complete DTV has taken place, a converter will be required to receive DTV
signals and change them to the analog format of these older types of
televisions. However, these DTV-to-analog converters will not produce true DTV
quality.
Analog televisions are now commonly referred to conventional televisions.
See also DTV.