VTR signal processing circuit

Abstract

In a VTR signal processing circuit, a first reproduced color under signal and a second reproduced color under signal obtained by delaying by one or two horizontal period in synchronism with a predetermined clock signal are supplied to the first and second frequency converter circuits respectively, a frequency signal having frequency 2n times that of a carrier used in frequency conversion for converting a frequency of the reproduced color under signal into a frequency corresponding to a standard color signal is produced by an oscillator circuit, this oscillation frequency is divided such that it becomes the above mentioned carrier frequency, four carriers having phases degree, degrees, degrees, and degrees respectively are produced, the four carriers are selectively output and supplied to the first and second frequency converter circuits (such that an output signal of the first frequency converter circuit and an output signal of the second frequency converter circuit become in phase or inverted phase, and a color cross-talk between tracks is removed by adding the both output signals or subtracting one of the output signals from the other.

Description

[0001] The present application is a divisional application of the patent application of the same name with an application date of March 10, 1998 and an application number of 98108243.2. technical field [0002] The present invention relates to a VTR (Video Tape Recorder) signal processing circuit, and in particular to a technique effectively used in an apparatus including a frequency converter part of a double main converter system by utilizing two frequency converter circuits And a delay circuit such as a CCD (Charge Coupled Device) eliminates the cross-color contained in the reproduced color under signal. Background technique [0003] Figure 5 is a block diagram of the frequency converter portion of a conventional double converter system of the prior art. [0004] Figure 6(a) is a waveform diagram of a conventional delay operation of a prior art color video signal when operating steadily. [0005] FIG. 6(b) is a waveform diagram of a conventional delay operation of a colo...

AI Technical Summary

Problems solved by technology

[0009] When the delay element is one that uses a glass delay line, there is a problem: the glass delay line itself is a rather large device mounted on a circuit board and it is expensive

With this phase change, the elimination effect of the cross-color of adjacent tracks is reduced, causing a reduction in image quality, and when the phase is reversed, the eliminated signal component results in a colorless image

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