| 摘要 |
The frequency-modulated oscillator, intended to provide at least one of the chrominance sub-carriers, with specified quiescent frequency, of a SECAM coder, is provided with a quiescent frequency servocontrol loop. This loop comprises a reference oscillator 10, a phase comparator 11 receiving the reference frequency and the frequency of the oscillator 12, and a sampler 15 actuated at half the line flyback frequency. The loop is provided in order to apply a multiplicative correction to the oscillator 12 so as to adjust not only the quiescent frequency, but also the slope of the frequency-modulation characteristic. <IMAGE>
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