| 摘要 |
PURPOSE:To prevent the generation of moire and to obtain a demodulated output without phase and amplitude distortions, by sampling an input information signal once, PM-modulating and recording a carrier wave signal with a sampled sampling signal as a modulation signal, and performing signal processing in the reversing process (demodulation process) as the modulation process. CONSTITUTION:A PM chrominance carrier signal Sg is reproduced at a magnetic head Hpc, and a reproduced output Sh is shaped in the same waveform as that at recording with a limiter 32. This limiter output Si is applied to a PM demodulation circuit 30. In this invention, the circuit constitution is devised so as to demodulate the original signal at the inverted process as the modulation process, then a limiter output Si and an output Si' delayed at a delay circuit 33 slightly are applied to an exclusive OR 34 to form a pulse Sj having the same information as the phase information of the PM chrominance signal and the pulse Sj is applied to a phase detection circuit 35. |
