彩色电视机内部的单元电路种类很多,除了有黑白电视机所有的电路外,还具有各种自动控制性能的特殊电子电路。一.自动亮度限制(ABL)电路。作用是防止高压硅堆回路过载,不使显象管阴极射束电流过大和控制光栅亮度,使其不超过极限值。这种保护电路,可以延长显象管的使用寿命;二.自动清晰度控制(ARC)电路。在收看彩电节目时,彩色副载波对图象有一定程度的干扰,会在荧光屏上造成网纹状干扰。为了减小这种干扰,在亮度通道中加有副载波4.43MHZ陷波器。它只在接收彩色信号时工作,对接收黑白信号不起作用,不影响黑白图象的清晰度;三.自动杂波消除(ANC)电路。作用是保护同步不受干扰,保持同步扫描的稳定性;四.自动饱和度控制(ACC)电路。它能保持色 There are many kinds of unit circuits inside a color television set. In addition to all the circuits of a black-and-white television set, there are special electronic circuits with various automatic control functions. One. Automatic brightness limit (ABL) circuit. The role is to prevent the high-voltage silicon reactor overload circuit, the CRT cathode beam current is not too large and control the brightness of the grating, so that it does not exceed the limit. This protection circuit, you can extend the life of the picture tube; 2. Automatic Clarity Control (ARC) circuit. When watching TV programs, the color subcarriers interfere with the image to a certain degree and cause reticular interference on the screen. To reduce this interference, a subcarrier 4.43 MHz notch filter is added to the luminance channel. It only works when receiving color signals, does not work for receiving black and white signals, does not affect the clarity of black and white images; 3. Automatic clutter elimination (ANC) circuit. The role is to protect the synchronization from interference, to maintain the stability of simultaneous scanning; four automatic saturation control (ACC) circuit. It can keep color