| 摘要 |
PURPOSE:To eliminate up of a picture due to the mixing of a signal without causing the increase of cost and power consumption by providing a ring counter that makes one round at the frequency of odd number times of half of the horizontal scanning frequency of a television and a logical circuit that combines signals outputted from each part of the ring counter generate the reference signal of a horizontal synchronizing signal. CONSTITUTION:The waveform outputted by the ring counter output 53 rises up to ''1'' and at the 3rd clock falls down to ''0'' at the 38th clock. Similarly, the waveform outputted by the ring counter output 34 rises up at the 33th clock and falls down at the 68th clock. The two waveforms 3Q, 33Q is ANDed. A 13 times counter 35 is connected to the Q output of first step flip flop of the ring counter and count the risie, and controls which one is to be outputted out of the pulses made by the ring counter output waveforms 3Q, 33Q. A 13 times counter is used for the counter 35 because the ring counter makes 13 times of round to make the succeeding horizontal scanning and phase coincide. |
