有线电视用户放大器设计和调试的几点经验

传统的有线电视用户放大器设计和调试时，受到用户放大器失真指标分配值的限制，往往只能采用较大幅度范围的输出电平值和输入电平值，这种设计调试方法不利于提高放大器的用户分配效率，难以保证其载噪比指标。根据放大器输出电平改进型计算公式，提出以改变放大器的输出斜率的方法来调节其失真指标，从而可以在不同的条件下，都能够使用户放大器的输出电平设定在其“标称输出电平”上，使输入电平设定在“标称输入电平”上。这种新的设计调试方法，在保证用户放大器失真指标的前提下，既提高自身的分配效率、稳定载噪比指标，又能提高前级放大器带负载的能力，方便间距的设计。

Experience of Designing and Debugging CATV Distribution Amplifier

During the designing and debugging of traditional CATV distribution amplifiers, a wide range of input levels and output levels have to be applied due to the limitation of distortion index, which is disadvantageous to improve the distribution efficiency and C/N index of the amplifier. According to an improved formula for output level of amplifiers, the author suggests an approach of adjusting output slope. The output level above nominal output level can be maintained the distortion index by modifying , and so can the input level under nominal input level. This new approach can improve the amplifier＇s distribution efficiency and stabilize the C/N index, as well as increase its loading capacity and simplify the spacing design.