Abstract: A luminance signal processing circuit includes a delay circuit for delaying a signal by one horizontal period, a first adder for adding an input signal and an output signal of the delay circuit, a filter circuit for passing a specified frequency band of an output of the first adder, a first coefficient circuit for multiplying an output of the filter circuit with a specified coefficient, a second adder for adding an output of the first coefficient circuit and the input signal to use the sum output signal as the input signal to the delay circuit, a subtracter for subtracting the output signal of the delay circuit from the input signal of the delay circuit, an amplitude limiter for limiting the amplitude of an output of the subtracter, and a second coefficient circuit for multiplying an output of the amplitude limter with a specified coefficient.

Abstract: In a tape recorder, when a magnetic tape changes its transportation speed for special reproduction, either one of a phase reference signal and a magnetic tape transportation phase signal representing the transportation phase of the magnetic tape is delayed by a delay circuit so that the signal not passing therethrough is compared with that having passed through the delay circuit, at which time the delay time of delay circuit is changed corresponding to the transportion speed of the magnetic tape so as to carry out phase control, thereby obtaining the optimum tracking in the reverse normal, double, and triple speed reproduction modes.

Abstract: A video tape recorder has a simple helical-scan construction capable of variable-speed reproduction free from noise bars on reproduced images at desired speeds ranging from a normal speed in reverse reproduction to threefold normal speed in forward reproduction.

Abstract: In a video tape recorder of the helical scan type, two auxiliary magnetic heads having different azimuth angles are provided in the vicinity of two main magnetic heads. The main and auxiliary magnetic heads have their tracks aligned so as to compensate for the reduced period of the reproduction signal of the main magnetic heads during high speed reproduction by using the reproduction signals of the auxiliary magnetic heads. Thus, blur free high speed reproduction pictures may be realized, and, at the same time, a dancing picture correction during still reproduction may be facilitated.

Abstract: A positionable element driving circuit for driving a positionable element compensates the supplied voltage-position characteristics of a bimorph type piezoelectric element which is used in a track following type video tape recorder/reproducer and which displaces the position of a video head. The supplied voltage to the bimorph type piezoelectric element is generated by an operational circuit which detects the track position of the video head. The circuit of the present invention compensates for the non-linearity and maintains the track following when the video tape recorder/reproducer is switched from one mode to another, e.g. from a still motion mode to a quick motion mode.

Abstract: A recording time mode detector for automatically detecting the recording time mode of reproducing video tape. This detector is constructed of a counter which counts the number of rotations of the capstan which drives the reproducing video tape and is reset by a reproduced control signal. The recording time mode is detected by the count stored in the counter.