Rules for the Technical Engineering of Cable Radio and Television Systems Article 21
The differential gain of the head-end analog television modulator shall be less than 10%, difference phase should not exceed ±5 degrees.
中文原文 有線廣播電視系統工程技術管理辦法第21條
頭端類比電視頻道電視調變器之差動增益應小於百分之十、差動相位不得超過正負五度。