| 摘要 |
PURPOSE:To discriminate quickly a low range conversion method of a color signal by reproducing SECAM system color television signals whose color signals are frequency converted into low range and stored from a recording medium and by detecting frequency deviation quantity in an ID area of a reproducing signal before the color signal is demodulated. CONSTITUTION:When a color signal which is converted into low range is extracted its ID area alone by an ID gate circuit 13, only fDR and fDB which are converted into low range are obtained. When this signal is put into a frequency- voltage transducer 14, a large signal is obtained when frequency deviation is large and a small signal is obtained when deviation is small. Therefore, when frequency deviation is a balanced modulation methode of 150kHz and a dividing method of 40kHz, there occurs a big difference in output of a frequency-voltage transducer 14. Controlling a demodulating system 12 by detecting this difference by a comparator 15 makes the device function as a discrimination circuit.
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