An experimental Half Inch Hi-Vision Digital VCR has been developed, which has the ability to record 2-Hours using 11μm thickness tape, 0.47μm recording wavelength, 12.7μm track width, small size cassette. We explain fundamental policy about Main Specifications, Specifications of VCR, and Tape Format. Next we describe the construction and characteristics of the Tape Transport Mechanism correspond to 11μm thickness thin tape, the construction of 40mm Diameter small drum, the construction and characteristics of high performance FeTaN Magnetic Head, and the Software Servo Control mechanism.

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We developed the experimental Half Inch Hi-Vision Digital VCR. This paper reports its Signal-Process ing System. At first, we explain the Intra-Field Fixed Length DCT Algorithm, which compresses 594Mbps data of Hi-Vision into 125Mbps. Next we describe the Error-Correction System, 1,7Codes, PR (1,1) +3Level ・4States Viterbi Decoder. Our experimental system has (2-Heads)*(2-Channels), and total recording bit rates is 160Mbps. At last, we show the Performance, Eye-Pattern, Reproduced-Picture-Image. Bit Error Rates is less than 10^<-5>, and the quality of Reproduced Picture is sufficient for Home-Use VCRs.

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A magnetic recording/reproducing system for a Digital VTR whose recording bit rate is 40Mbps has been studied by using the PCM audio system of the consumer HD-VTR. The PCM audio system of this VTR achieves a recording bit rate of 38.592Mbps by recording 8-10 modulated signals on a MP tape with four heads, where a minimum recording wave length is 0.6μm. This paper describes the high frequency circuit design of PLL circuit, etc. for a high recording bit rate system, the S/N ratio of the system and also degradation of the S/N ratio by cross-talk and overwrite. The feasibility of a high recording bit rate system of 40Mbps has been confirmed from this study.

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We have developped a motion-adaptive field conversion system for nonstandard speed play of a D-2 composite VTR. It is realized by a combination of a Y/C separation technique and a line-interpolation technique which adaptively use inter-field signals. And we have developped a new motion detecting method too. This method add a inter-field motion detection by level comparison to a conventional method using temporal-spatial filter. With those techniques it has become possible to improve periodical displacement of vertical transition, deterioration of vertical resolution, flicker in chrominance signal and so on. So Picture quality as good as normal play mode has been obtained in nonstandard-speed play mode.

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