CHANNEL CONTROL CIRCUIT OF SATELLITE BROADCASTING TV

摘要

The channel sync circuit is capable of receiving either TV signal or sattelite signal with only one PLL(Phase Locked Loop). The system is different from the old one in using a PLL (300) and a frequency divider (40). The divider makes a load oscillating frequency (fL2) from TV tuner (50) and a fL1 from sattelite tuner (20) to use same PLL by dividing fL1 into two. Then micro-computer (200) program is simple, which means fast processing and simple circuit design.