Abstract: The invention relates to a method and an arrangement for compensating scanning disturbances on optical recording media such as occur in a control loop of a playback or recording unit, in particular as settling amplitude after a disk disturbance and are caused by scratches or dirt on the optical recording medium. In order to compensate the scanning disturbances, a follow-up signal counteracting the settling amplitude is coupled into the control loop as additional offset as a function of the frequency of the occurrence of a disk disturbance for a prescribed time interval. The follow-up signal is coupled into the control loop with a step width that is increased from revolution to revolution on the recording medium until the change in the direction of the settling amplitude of the control loop. Large follow-up signal values are produced in a stepwise fashion in the event of absence of the disk disturbance, in order to avoid large variations in the follow-up signal value.

Abstract: The invention relates to a method and an arrangement for compensating scanning disturbances on optical recording media such as occur in a control loop of a playback or recording unit, in particular as settling amplitude after a disk disturbance and are caused by scratches or dirt on the optical recording medium. In order to compensate the scanning disturbances, a follow-up signal counteracting the settling amplitude is coupled into the control loop as additional offset as a function of the frequency of the occurrence of a disk disturbance for a prescribed time interval. The follow-up signal is coupled into the control loop with a step width that is increased from revolution to revolution on the recording medium until the change in the direction of the settling amplitude of the control loop. Large follow-up signal values are produced in a stepwise fashion in the event of absence of the disk disturbance, in order to avoid large variations in the follow-up signal value.

Abstract: A resilient scanning or recording head support made of deformable material comprising a resilient molded part being step like shaped and resiliently deformable in at least one direction and/or through an angle. This construction accommodates deflection of the scanning head analogously to a parallel guide, in a straight line as well as through at least one angle deviating from the preferred directions of the parallel guide.

Abstract: Apparatus for reproducing coded audio signals includes interpolation circuitry for substituting interpolated signal values for erred or lost audio signal. To minimize undesirable audible artifacts which may be introduced into the audio signal by virtue of the substitution process, the rate of substitution is monitored. When the rate of substitution exceeds a predetermined rate, the higher frequency components of the audio signal, including the substituted values, are attenuated.

Abstract: With an optical playback device, for example, with a compact disk player, care should be taken to see that the light beam scanning the data radiates as perpendicular as possible onto the disk. However, as a consequence of disk slap or chattering, the radial and the tangential angles alter during every revolution of the disk. As a result of the tolerances in the disk and the device, the optical axis deviates from the perpendicular in many cases. In order to regulate the radial angle .phi.R and the tangential angle .phi.T, under which the light beam strikes the disk, the data signal is demodulated in an amplitude demodulator. The regulating signal UR=C* sin .phi.* cos .alpha. for the radial angle .phi.R and the regulating signal UT=-C* cos .phi.* sin .alpha. for the tangential angle .phi.T are generated from the amplitude C and the phase position .phi. of the demodulated data signal.

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.