JPH06165216A - Chrominance signal recording circuit - Google Patents

Abstract

PURPOSE:To automatically record different chrominance signals with the chrominance signal processor of one system by controlling a switching means, and turning a signal recording processing circuit into a state corresponding to the color sub-carrier frequency of an input video signal. CONSTITUTION:This circuit is equipped with a video signal input 4 for which a 3.58MHz video signal or a 4.43MHz video signal is inputted, recording circuit 5, first crystal vibrator 6 which sets the recording circuit 5 so that the 3.58MHz video signal can be recorded, and a second crystal vibrator 7 which sets the recording circuit 5 so that the 4.43MHz video signal can be recorded. Also, the circuit is equipped with a switching circuit 8 which selects one of first and second crystal vibrators 6 and 7, and connects it with the recording circuit 5, and a microcomputer 9. Then, when the generation of a color killer signal is detected, the microcomputer 9 changes a command outputted since then. At this time, the switching circuit 8 selects the second crystal vibrator 7, and the recording circuit 5 is turned to the state in which the 4.43MHz video signal can be processed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color signal recording circuit for recording video signals of different color subcarrier frequencies.

[0002]

2. Description of the Related Art An NTSC video signal having a color subcarrier frequency of 3.38 MHz (hereinafter referred to as "3.
A video tape recorder capable of recording both video signals of a 58 MHz video signal ") and an NTSC video signal having a color subcarrier frequency of 4.43 MHz (hereinafter," 4.43 MHz video signal "). Therefore, conventionally, as shown in FIG. 3, a recording circuit 1 for recording a 3.58 MHz video signal and a recording circuit 2 for recording a 4.43 MHz video signal are provided, and switching is performed when a color killer signal is output from the recording circuit 1. The switch 3 is switched from the terminal a to the terminal b, and the video signal of the recording circuit 2 is output.

[0003]

However, the above-mentioned conventional circuit has a drawback that it requires two systems of recording circuits.

The present invention therefore seeks to overcome such drawbacks.

[0005]

According to the present invention, in a video recorder capable of recording a plurality of video signals having different color subcarrier frequencies, a signal recording processing circuit and a recording signal of the signal recording processing circuit are determined. A recording signal setting means, a switching means for switching the recording signal setting means stage, a color killer signal obtained from the signal recording processing circuit, and controlling the switching means to input the signal recording processing circuit to the input video signal. And a control means for controlling the color subcarrier frequency.

[0006]

According to the above means, when the color killer output from the recording circuit is received, the control means switches the oscillation frequency setting means for determining the recording signal of the signal recording processing circuit.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a block diagram of a color signal recording circuit of a video tape recorder embodying the present invention, where 4 is 3.58.
MHz video signal or 4.43 MHz video signal input video signal input terminal, 5 is a signal recording processing circuit,
Reference numeral 6 is a first crystal oscillator for setting the signal recording processing circuit 5 so that it can record a 3.58 MHz video signal, and 7 sets the signal recording processing circuit 5 so that it can record a 4.43 MHz video signal. Is a changeover switch circuit for selecting one of the first and second crystal oscillators 6 and 7 and connecting it to the processing circuit 5, and 9 is a microcomputer.

Next, the operation of FIG. 1 will be described with reference to the flowchart of FIG.

First, when the video tape recorder is powered on, the microcomputer 9 sends a command for receiving a 3.58 MHz video signal to the signal recording processing circuit 5 for initialization (S1).

When the signal processing circuit 5 receives such a command, it is set to receive the 3.58 MHz video signal. At this time, the changeover switch circuit 8 selects the first crystal unit 6. As a result, the signal processing circuit 5 is set to 3.
The 58 MHz video signal can be processed.

Thereafter, the microcomputer 9 checks in step 2 whether or not the color killer signal is generated from the signal processing circuit 5, and if the color killer signal is not generated, the same command as the command currently being sent is sent. Continue (S3).

When it is detected in step 2 that a color killer signal is generated, the command issued so far is changed (S4). That is, if the command that has been issued so far is a command for a 3.58 MHz video signal, a command for selecting a 4.43 MHz video signal is output. The generation of the color killer signal means that a signal different from the setting state is input.

When the signal processing circuit 5 receives such a command, it is set to receive the 4.43 MHz video signal.
Select the crystal oscillator 7. As a result, the signal processing circuit 5 becomes ready to process the 4.43 MHz video signal.

[0015]

As described above, according to the present invention, there is an advantage that different color signals can be automatically recorded by one color signal processing circuit.

[Brief description of drawings]

FIG. 1 is a diagram showing a color signal recording circuit embodying the present invention.

FIG. 2 is a diagram showing a flowchart for explaining the operation of FIG.

FIG. 3 is a diagram showing a conventional color signal recording circuit.

[Explanation of Codes] 4 Video Signal Input Terminal 5 Signal Processing Circuit 6 First Crystal Resonator 7 Second Crystal Resonator 8 Changeover Switch Circuit 9 Microcomputer

Claims (1)

[Claims] 1. A video recorder capable of recording a plurality of video signals having different color subcarrier frequencies, a signal recording processing circuit, recording signal setting means for determining a recording signal of the signal recording processing circuit, and the recording. Switching means for switching the signal setting means, receiving a color killer signal obtained from the signal recording processing circuit, and controlling the switching means to bring the signal recording processing circuit into a state according to the color subcarrier frequency of the input video signal. And a color signal recording circuit including: