An automatic frequency control tracks a television signal before and after a period of interruption. The automatic frequency control comprises a voltage controlled feedback loop including a voltage controlled local oscillator (18) and a mixer (20) for mixing the output of the oscillator (18) with the TV signal. The output of the mixer (20) is filtered to remove unwanted components of the mixed signal and to equalize sidebands of the television signal. The output of the filter (24) is supplied to a detector (30) which is tuned to a component of the television signal, and produces a voltage corresponding to the frequency of the component. The output of the detector (30) is supplied to the voltage control input of the local oscillator (18) to track the television signal component. Circuitry (71, 72) automatically senses the absence of the TV signal component from the mixer (20), and automatically applies a reference voltage (VR) to the voltage control input of the oscillator (18) when the TV signal component is absent. The detector (30) is operative to detect the television signal component following the application of reference voltage (VR to the oscillator so that when the television signal returns, the detector (30) is capable of tracking it.
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