A method and apparatus for varying track recording speed to maximize host-to-tape data transfer rates is presented. Variable data transfer rates of host systems and networks are accommodated by continually adjusting the tape speed to match the tape drive to the host's actual transfer rate. The speed of the tape is adjusted according to both the level of data present in the tape drive data buffer and whether the current mode of the drive is write mode or read mode. In the preferred embodiment, when the tape speed is accelerated or decelerated while writing a number of data track pairs to tape, a predetermined number of dummy track pairs are first written to tape at the current speed. On the next write head phase after the speed is increased or decreased as appropriate while the read heads are over the track, a predetermined number of dummy track pairs followed by more data track pairs are written to the tape at the new speed.

A video tape recorder has a drum for winding a magnetic tape therearound, a capstan motor and a drum motor linked with the drum, both motors for traveling the magnetic tape, and two rotary magnetic heads arranged adjacent to each other relative to the magnetic tape and having two different azimuth angles. One reproduced signal of higher signal level is selected from two modulated signals reproduced by the two magnetic heads to output a detected reproduced signal. Sampling signals are generated each having a signal level corresponding to a signal level of the detected reproduced signal on the basis of the reproduced signal obtained by the selected magnetic head, only during a period while a predetermined one of the two magnetic heads is being selected in response to a head select signal, at each of time intervals obtained by dividing one vertical scanning period into a two or more natural number N. A central axis of the drum is inclined in such a way that the respective signal levels of the sampling signals satisfy a predetermined relative relationship with respect to one another, when recorded signal is reproduced by traveling the magnetic tape at a travel speed different from another travel speed of the magnetic tape in recording operation. And, rotation phase of the capstan motor is changed relative to a reference drum rotation signal of the drum motor.

An envelope is detected from each of a plurality of reproduced video FM signals successively read out from a magnetic tape, and a shape change of the envelope in one vertical scanning period is detected in a control microcomputer. In cases where the shape of the envelope is flattened, the flatness indicates that an inclination angle of a rotational drum is appropriately set and a scanning locus of a magnetic head attached on the rotational drum agrees with a track formed on the magnetic tape. In this case, a reproduced image having no noise is obtained. Therefore, the number of increase/decrease changes in the shape of the envelope is detected as a shape value. In cases where the shape value is high, the inclination angle of the rotational drum is largely and repeatedly changed until the shape value becomes low. In contrast, in cases where the shape value is low, the inclination angle of the rotational drum is slightly and repeatedly changed until the envelope shape is flattened. Accordingly, any noise does not occur in the reproduced image regardless of whether a magnetic recording and reproducing apparatus is used in interchangeable reproduction or self-recording/reproduction.

A tape guide angle controlling apparatus for controlling an orientation of a tape guide in a magnetic tape recorder-player includes a main base, a shaft bushing provided in the main base and having a shaft hole formed in the center thereof, a tape guide arm having at one end portion thereof a rotation shaft rotatably inserted into the shaft hole and at the other end portion thereof having a tape guide, a tape guide horizontal-rotating mechanism for horizontally rotating the tape guide arm, and a tape guide vertical-operating mechanism driven by the tape guide horizontal-rotating member for vertically moving the tape guide arm. The apparatus slants the tape guide which guides a magnetic tape in a reverse running mode, thereby improving the magnetic tape running operation in a reverse running mode.

A video cassette recorder, in which the head-drum angle is controlled by a control voltage which varies according to the tape speed detected from the frequency or a capstan motor applied by a frequency detecting portion at a first stage. Then, based upon the Fuzzy theory, the video head of head-drum can be maintained at a constant angle with the pitch (P) of a video tape independent of the tape speed by reproducing the control voltage by means of a detected membership function detected according to the gain difference (G) coming from a gain detecting portion.