Victor Company of Japan, Limited

Takao Kawasaki

Yukinobu Ishigaki

Yutaka Haramoto

Kaoru Totsuka

Satoru Nagashima

A digital recording apparatus has a transporter and processor. (1). Long play mode: The transporter rotates heads and transports a recording medium at each first speed. The processor converts a first input signal supplied at a normal transfer speed with A/D conversion at a first sampling frequency to generate a first data of a quantization levels, converts the first data to a second data of a quantization levels with a first clock frequency and processes the second data which is supplied to the heads so as to be recorded in the medium. (2). High recording mode: The transporter rotates the heads and transports the medium at each second speed which is N times faster than the first. The processor has a converter to convert a second input signal supplied at a transfer speed which is N times faster than the normal to a third signal having a second sampling frequency which is N times higher than the first and to process the third signal with a second clock frequency which is N times higher than the first to supply the third signal to the heads so as to record the third signal in the medium.

Digital recording/reproducing apparatus

A servo circuit for a capstan motor has an element for recording a position detecting signal on a medium transported by the capstan motor, a magnetic head for reproducing the position detecting signal, a position detecting circuit for detecting a position error signal, a pulse generator for a pulse signal, a velocity detecting circuit for a velocity error signal, a phase comparator for comparing the phase of a clock signal and pulse signal and for outputting a phase error signal, a switch for selectively outputting the position error signal or the phase error signal, and a velocity control element for controlling the capstan motor by a velocity control signal. The servo circuit comprises a signal holding element connected in series to a signal supply path from the position detecting circuit to the velocity control element via the switch; a comparator circuit for outputting a detection signal when the phase error signal is within a predetermined level range; a holding control element responsive to the detection signal for controlling the signal holding element in a manner that in the case where the servo circuit is transited to a recording mode, until a transporting speed of the medium sufficiently reaches a predetermined speed, the signal holding element is caused to be in a passing state and then to enter a holding state, and when the signal holding element is caused to return to the passing state.

Servo circuit for capstan motor

In a noise reduction system including a compressor and an expander having a complementary frequency response characteristic to the frequency response characteristic of the compressor, the compressor includes a high frequency emphasis variable frequency filter and a low frequency emphasis variable gain filter which are connected in a series circuit between input and output terminals and which respectively vary their parameters in response to the respective high and low frequency components of the compressor output. The expander includes a high frequency de-emphasis variable frequency filter and a low frequency de-emphasis variable gain filter which are connected in a series circuit between input and output terminals and which respectively vary their parameters in response to the respective high and low frequency components of the expander input.

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Gunma, Japan

Takao Kawasaki