公开(公告)号：US3688037A

公开(公告)日：1972-08-29

申请号：US3688037D

申请日：1970-09-30

Applicant: RCA CORP

Inventor： IPRI ALFRED CHARLES

IPC: H04N5/12 ,  H04M5/06

CPC classification number: H04N5/12

Abstract: A vertical phase synchronization system for a television receiver develops vertical deflection frequency signals by employing a resetable frequency divider circuit to count down clock pulses having a frequency twice the horizontal deflection frequency. The resultant internally generated vertical signals are compared with received external vertical synchronization signals. If a phase error exists, a pulse width detector to which external sync pulses subject to noise are applied, is activated. When activated, the pulse width detector develops a reset pulse for the frequency divider to lock the phase of the internally generated vertical signals with external vertical sync in response only to a pulse of the requisite vertical sync pulse duration, thereby providing noise immunity for the system.

Abstract translation: 用于电视接收机的垂直相位同步系统通过采用可复位分频器电路对具有两倍于水平偏转频率的频率的时钟脉冲进行倒计数来产生垂直偏转频率信号。 所得到的内部产生的垂直信号与接收的外部垂直同步信号进行比较。 如果存在相位误差，则施加外部同步脉冲受到噪声的脉冲宽度检测器被激活。 当激活时，脉冲宽度检测器产生用于分频器的复位脉冲，以便只响应必需的垂直同步脉冲持续时间的脉冲来锁定内部产生的垂直信号与外部垂直同步的相位，从而为系统提供抗噪声 。