Signal reproducing device

Abstract

Abstract PURPOSE: To reproduce a picture of even quality covering the entire disk circumference in a disk signal reproducing device which uses a double limiter circuit, by detecting the radius-directional position of a discoid redording medium and then by exercising level control over a side band component applied to an adder according to the detection output. CONSTITUTION: For example, when FM deviation occurs as shown in the figure, HPF104 has the characteristic of waveform (c) and only a carrier component is extracted. Since the carrier component having passed through HPF104 is led to the 1st limiter circuit 106, there is not a large difference between the external and internal circumferences of the disk with the sufficient gain of limiter 106. On the other hand, LPF105 has the characteristic of waveform (d) and a side band component having passed through LPF105, if a change in reproduction output between the external and internal circumferences of the disk would be caused, has a difference in magnitude between the external and internal circumferences led to the 2nd limiter circuit. For the purpose, the amplification factor of the side band component at its internal circumference is made greater than at the external circumference by amplification factor control circuit 108 to make even the quality of pictures at the external and internal circumferences. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Shunji Kanamaru
• 👤 Hideo Okamura
• 👤 Akira Ichinose

Bibliographic Details