Victor Company of Japan, Limited

Kazuo Yamada

Yasuaki Watanabe

Hiroji Ibaraki

An information signal recording medium reproducing apparatus comprises an equalizer supplied with a frequency modulated composite video signal picked up from an information signal recording medium, a frequency demodulator for frequency-demodulating an output signal of the equalizer into a composite video signal, a synchronizing signal separating circuit for separating a horizontal synchronizing signal from the composite video signal, and a switching signal generating circuit for forming a switching signal from the horizontal synchronizing signal. The equalizer is supplied with the switching signal and has such a circuit construction that a frequency at which an output level versus frequency characteristic of the equalizer has a peak is reduced responsive to the switching signal during a predetermined time period in a vicinity of the front edge of the horizontal synchronizing signal to correct a distorted waveform of the frequency modulated composite signal caused by defects in the information signal recording medium.

Information signal recording medium reproducing apparatus with an

A capacitance detector for detecting the information recorded in the form of a series of microscopic pits on a capacitance disc record. The detector comprises, within an outer conductor, a dielectric support, an oscillator having a first line conductor on the support for generating microwave energy, a coaxial resonator having a second line conductor on the dielectric support, the second line conductor being coupled to the electrode of a capacitance detection stylus. Means are provided for inductively coupling the microwave energy from the oscillator to the resonator. This coupling means comprises a loop having a first section inductively coupled with said first line conductor and a second section inductively coupled with said second line conductor, and a capacitor connected from an intermediate point between the first and second sections to ground, so that the microwave energy coupled to the second line conductor is modulated in amplitude with capacitance variations corresponding to the microscopic pits. An amplitude demodulator is provided for demodulating the amplitude-modulated energy to derive a signal representing the capacitance variation on the record.

Detector circuit for capacitance disc records

A rotary recording medium reproducing apparatus comprises a rotary recording medium in which an information signal is recorded as variations in electrostatic capacitance, wherein the rotary recording medium is rotated, a reproducing stylus for making contact with and relatively scanning over the recording surface of the rotary recording medium upon reproduction, having an electrode for detecting the information signal as variations in electrostatic capacitance, a reference potential part functioning as a reference potential point, a first direct-current connection path for connecting the rotary recording medium with the reference potential part for direct-current, and a second direct-current connection path for connecting the reproducing stylus with the reference potential part for direct-current. The second direct-current connection path including a signal pickup circuit.

Growing community of inventors

Noda, Japan

Kazuo Yamada