| 摘要 |
<p>PURPOSE:To obtain the inexpensive device by using the signal processing circuit of the MUSE signal system and that of the NTSC system in common so as to decrease the circuit scale. CONSTITUTION:When a MUSE signal is inputted from an input terminal 1, a signal discrimination circuit 19 selects a switch 22 and an outputted signal is A/D-converted by an A/D converter 2, a 1st frame pulse detection circuit 16 detects a frame pulse of the MUSE signal and a PLL circuit 4 recover a correct sampling clock based on phase information in the MUSE signal. Moreover, when the NTSC signal is inputted from an input terminal 9, the signal discrimination circuit 19 selects the switch 22 to the position of the input terminal 9, the outputted signal is inputted to the A/D converter 2, and the PLL circuit 4 is not operated on the other hand, and a clock with a sufficient speed is applied for the A/D-conversion to the NTSC signal. The different processing circuit is used in common in response to the input signal and the operation is switched in response to the input signal.</p> |
