| 摘要 |
PURPOSE:To reduce buzz, by setting so as to offset a characteristic of a phase modulation component of an inter-carrier signal by ea modulation characteristic of a phase modulator. CONSTITUTION:A video signal is applied through a sound trap circuit 7 consisting of a solid resonator and a coil, and a resistance R2. When magnitude of this video signal is varied, capacity of a variable capacity diode C1 is varied, by which magnitude (ec, er) of an inter-carrier signal developing across both a diode C1 and a resistance R1 is varied, therefore, phase phi of a voltage value eo of an inter-carrier signal which is obtained by an output terminal 0 is varied as shown in the figure. Accordingly, when a value of each element of this phase modulator is selected suitably, a phase modulation characteristic which is obtained by the output terminal 0 can be varied as shown by a chain line. |
