Abstract: A phase control circuit in which a first phase comparator compares an input frequency with a reference frequency. The output of the first phase comparator is connected to a controlled oscillator through a control stage. A second control stage is also connected to the input of the controlled oscillator which has an output connected to a second phase comparator which receives also the reference frequency at an input. The output of the second phase comparator is connected to an input of the second control stage. The first control stage is separated from the controlled oscillator to compensate the circuit automatically. The second control stage varies its output until the frequency at the controlled oscillator output equals the reference frequency. The second control stage maintains this level subsequent to compensation independent of the output from the second phase comparator, and the first control stage is reconnected to the input terminal of the controlled oscillator.