使用转盘式频道转换开关的1～12频道老式电视机要接收增补频道,以改动各频道线圈重新调谐的办法比较实惠。因为一般省会城市或中等城市对1～12频道的利用方法,大体上是空出3个频道供转播中央一套及省台和本市市台直播等无线发射之用。该三个频道不发送有线电视台的信号。但是有线电视台还是要再安排另外三个频道来转发中央一台、省台和本市 The use of carousel channel switch 1 to 12 TV channels to receive additional channels to change the channel re-tuning of each channel is more affordable. Because the general capital city or medium-sized cities on the use of 1-12 channels, in principle, is empty of three channels for the broadcast of a central set and the provincial Taiwan and Taiwan city broadcast live and other wireless purposes. The three channels do not send cable station signals. However, the cable television station still has to arrange another three channels to forward the Central Taiwan, the provincial Taiwan and the city