无论分立元件或集成电路电视机,如果声图均有,但图像水平位置偏向左侧或右侧,荧屏一侧出现黑带(约占荧屏的四分之一左右),这种现象说明电源、高中频通道、视放、行输出电路均正常,是行扫描电路相位异常所致。控制行频相位的电路,只有AFC(自动频率控制)。该电路必须同时输入两个电信号才能正常工作;一个是幅度分离电路送来的行同步脉冲,另一个是由行逆程变压器反馈回来的行逆程脉冲,两者缺一不可。AFC电路(分立元件机)见附图所示。主要由鉴相、积分 Regardless of discrete components or integrated circuit television, if the sound image are, but the horizontal position of the image bias to the left or right side of the black side of the screen (about a quarter of the screen), this phenomenon shows that the power supply, High frequency channel, depending on the line, the output circuit are normal, the line scan circuit phase is abnormal. Circuit to control the line frequency phase, only AFC (automatic frequency control). The circuit must be simultaneously input two electrical signals to work properly; one is the line sync pulse sent from the amplitude separation circuit, and the other is the line back-pulse pulsed back from the line back-transformers, both of which are indispensable. AFC circuit (discrete component machine) See the attached figure. Mainly by Kam phase, integral