本文主要介绍电压合成方式及频率合成方式的调谐系统。近年来,由于数字技术及微处理器的应用,使电视接收机的调谐方式有了很大的发展,由过去改变电感值的机械式调谐方法过渡到利用变容二极管的电子调谐方式。但是,早期的电调谐对频道的选择是利用电位器预置, This article describes the voltage synthesis and frequency synthesis of the tuning system. In recent years, due to the application of digital technology and microprocessors, the tuning method of the television receiver has been greatly developed. The mechanical tuning method of changing the inductance value was used to transit to the electronic tuning method using varactor diodes. However, the early electrical tuning of the channel selection is the use of potentiometer preset,