| 摘要 |
PURPOSE:To eliminate secondary beats only by supplying a converted color signal separated from a reproduced signal to a double balanced modulator to form a frequency double the low carrier frequency, and adjusting the level and the phase of this signal. CONSTITUTION:The vonverted color signal from a low-pass filter 3 is supplied to a phase adjusting circuit 12, and an output fignal from the circuit 12 is to the double balanced modulator 13. An output signal from the double balanced modulator 13 is supplied to a tuning circuit 14. An output from the tunercircuit 14 is level-adjusted in a gain control amplifier 15 from which a cancelling signal is obtained. Such a cancelling signal is phase-inverted and supplied to an adding circuit 6. Accordingly, the secondary beats is removed from a reproduced brightness signal. The phase adjuting circuit 12 and the level adjusting circuit 15 do not require readjusting if once adjusted at the time of shipping as far as the recording and the reproduction are executed with the same VTR.
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