| 摘要 |
PURPOSE:To avert instability of an image screen and deterioration in vertical resolution even if the traveling speed in the stage of variable speed reproduction deviates from the (2N+1)-fold the standard speed by discriminating the range of the standard speed ratio to a reproducing speed, discriminating the coincidence and dissidence of odd and even of a video signal and reference signal and jumping a magnetic head according to both discriminated outputs. CONSTITUTION:A detecting circuit 15 for the traveling speed of a tape detects a standard speed ratio X to a traveling speed. A discriminating circuit 15A discriminates whether the detected output Z is in a range of 2N+1/2<=X<=2N+3/2 (N is an integer). Reproducing and reference vertical sinchronizing signals VPB, Vref are supplied from vertical synchronizing separating circuits 7, 11 to a discriminating circuit 15B for the coincidence and dissidence of odd and even of fields, by which the signals are discriminated. The outputs from both discriminating circuits are supplied to a storage means 15C, by the output from which switches SWA-SWC are cooperatively selected and controlled. If the X is within the above-mentioned range and odd and even are coincident, the constant signal from a means 17a for generating the constant signal is made to integer by an adder 13 and an A/D converter 18 and the output thereof is doubled by an amplifier 18b and is supplied as a jump command signal to a bimorph driving circuit 19. |
