Abstract: An apparatus is adapted to perform a method for recording and reproducing a digital signal in a track on a recording medium for reproduction at normal and trick play speeds. The method comprises the steps of processing the digital signal to form first and second record signals. The first record signal is recorded in a first part of the track. The second record signal is recorded in a second part of the track smaller than and separate from the first part of the track. The first and second record signals are reproduced from the first and second parts of the track.

Abstract: A digital video cassette recorder operates by the selection of predetermined replay speeds and the allocation of specific locations within each track from which data may be reproduced. These specific track locations are utilized during recording to place advance television image data for reproduction during trick play operation. The trick play image data is also reproduced during normal playback but may not be utilized. The specific track locations are selected to facilitate trick play operation at a plurality of speeds in both forward and reverse directions. Since the advanced television signal comprises a plurality of predicted frames, transition from trick play to normal speed replay requires a control function which is responsive to the reproduction, at normal replay speed, of an inter frame coded frame. Various methods of reproduced image transition are used for selecting both to and from trick play reproduction.

Abstract: In an orthogonal frequency division modulation (OFDM) apparatus and method, a transmitter produces a clock and a reference signal to provide an accurate phase in modulation of a carrier. A receiver is thus able to reproduce the reference signal, even if the signal-to-noise (S/N) ratio of the carrier is poor. The OFDM method includes the steps of AM-modulating a group of digital signals with a plurality of carriers, in which a reference signal is frequency-modulated at a symbol period, combining the AM-modulated carrier and modulating the combined carrier into a main carrier, detecting the main carrier by phase-locking the frequency-modulated reproduced reference signal with the transmitted reference signal and fast-Fourier-transforming the combined carrier to demodulate the digital signal.

Abstract: A transition enhancing circuit includes a tapped delay line which provides successively delayed replicas of the signal to be processed. A multiplexer, responsive to a signal transition, sequentially couples delayed signal from the center tap and taps more distant from the input of the delay line to an output terminal to effectively hold the initial value of the transition for approximately half the transition period. The taps at the input end of the delay line up to and including the center tap are then sequentially coupled to the output terminal to effectively advance, in time, the end value of the signal transition. The signal transition is thereby reduced to a time equivalent to the switching interval between taps.

Abstract: In a television apparatus, a line comb filtered first chrominance signal that is delayed by one horizontal interval and the line comb filtered first chrominance signal that is undelayed are formed from a baseband video input signal. A line comb filtered first luminance signal is also formed from the input signal. A signal that is representative of a difference between the chrominance signals is correlated with a high frequency signal component of the first luminance signal to form a control signal that controls a switching arrangement. The switching arrangement provides combed luminance and combed chrominance signals that are to be displayed in a video display. When the control signal is indicative of the corresponding signals being correlative, the switching arrangement provides, instead, corresponding uncombed signals so as to reduce the visibility of hanging dot condition.

Abstract: A video disc player apparatus having a signal pickup stylus secured to a stylus arm for recovering recorded signal from a disc record, wherein the stylus arm is mechanically biased by a spring force to produce a positive stylus-disc pressure, includes apparatus cooperating with the stylus arm to maintain the stylus-disc pressure generally constant in the presence of stylus-disc displacements normal to the disc surface. A permanent magnet is secured to the stylus arm with its interpolar axis transverse to the stylus arm and substantially parallel to the disc record. First and second coils, coaxially aligned are disposed on either side of the magnet and arranged with their axes parallel to the interpolar axis of the magnet. Energizing currents are applied to the first and second coils creating respective magnetic fields which produce forces repulsive to the pole of the permanent magnet proximate thereto.