ST 170:2004 - SMPTE Standard - For Television — Composite Analog Video Signal — NTSC for Studio Applications

(1.1) This standard describes the composite analog color video signal for studio applications: NTSC, 525 lines, 59.94 fields, 2:1 interlace with an aspect ratio of 4:3. (1.2) This standard specifies the interface for analog interconnection and serves as the basis for the digital coding necessary for digital interconnection of NTSC equipment. — NOTE - Parts of the NTSC signal defined in this standard differ from the final report of the Second National Television System Committee (NTSC 1953) due to changes in technology and studio operating practices.