本实施规程规定了用于525线/60场电视系统的黑白和NTSC彩色信号的2英寸四重视频磁带记录交换所需的记录信息参数。参数包括所有记录实践的视频预相位特性和记录的载波频率，以及实践SHBP的视频引导规范。定义的实践是:实践SHBP:该实践适用于彩色和单色信号。视频导频信号被添加到记录的信息中，以用作回放参考。规程HB:该规程适用于彩色和单色信号。 实践LBM:该实践仅适用于单色信号。（它被认为是过时的，仅供参考。）实践LBC:该实践适用于彩色和单色信号。它被认为是过时的，仅供参考。）

This practice specifies parameters of the recorded information essential to the interchange of 2-in quadruplex video magnetic tape recording of monochrome and NTSC color signals for 525-line/60-field television systems. The parameters include video preemphasis characteristics and recorded carrier frequencies for all recording practices and video pilot specifications for practice SHBP.Practices defined are:Practice SHBP: This practice is suitable for color and monochrome signals. A video pilot signal is added to the recorded information to be used as a playback reference.Practice HB: This practice is suitable for color and monochrome signals.Practice LBM: This practice is suitable only for monochrome signals. (It is considered to be obsolescent and is included for reference purposes only.)Practice LBC: This practice is suitable for color and monochrome signals. It is considered to be obsolescent and is included for reference purposes only.)