Asked by
kajol devgan
in
TV & Radio
at
1:49 PM on April 29, 2008
ajay bhutani's Answer
U.S. government and industry committee which defined the 525-line 60 (59.94) interlaced fields per second analog broadcast TV standard over 50 years ago. (This format is referred to as NTSC.) Of the 525 scan lines, 480 (give or take a few) contain the picture and the rest contain synchronizing information, hold the encoded closed caption text, and provide a time delay to move the electron beam back to the top of the screen. NTSC is used mainly in North America and Japan. Originally 30 frames per second, the standard was changed slightly to 29.97 frames per second at the time color was introduced since that change made it easier to incorporate the color information into what is now a composite video signal. The change was so small that practically all older TV sets continued to receive the signal properly without loss of vertical hold.
Answered at
3:54 PM on April 30, 2008
Read all answers
