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随着有线电视和卫星电视的开通，节目数量的不断扩大，尤其是增补频道的使用，使相当数量的电视机已不能适应现有电视节目的收看。而频道变换器是专门为有线电视系统设计的终端接收设备，它能覆盖有线电视网包括增补频道在内的６０个频道。利用频道变换器可准确地调到任一有线电视频道，并经频道变换器内的调制器变频到固定的频道（１频道，４９．７５ＭＨｚ）输出。该变换器中心是８０３１单片机，选台用数字频率合成。具有红外遥控，开关电视机电源，频道频率微调、定时自动关机、直呼、递增／递减、最后呼出等功能。本文简要介绍其原理与设计。
With the opening of cable television and satellite television, the number of programs has been constantly expanding. In particular, the use of additional channels has made it impossible for a large number of television sets to adapt to the existing television programs. The channel changer is designed for CATV system terminal reception equipment, it can cover the cable network, including additional channels, including 60 channels. The use of channel changer can be accurately transferred to any cable channel, and by the channel converter modulator frequency conversion to a fixed channel (1 channel, 49.75MHz) output. The center of the converter is 8031 microcontroller, channel selection with digital frequency synthesis. With infrared remote control, switching power supply, channel frequency fine-tuning, automatic shutdown at regular intervals, direct calls, incremental / decremental, the last exhale and other functions. This article briefly describes its principles and design.