JPH0490158A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To discontinue useless recording by automatically stopping the recording when a video signal is not inputted. CONSTITUTION:When a video signal S1 is inputted to a video input terminal T of the magnetic recording and reproducing device under a recording mode, a video signal detecting circuit 1 is not operated, and the video signal S1 is sent out as it is to a Y/C separating circuit 2. When no video signal is inputted to the video input terminal, this is detected by a video signal detecting circuit 1 and a detected signal S2 is transmitted to a system control circuit 4. A control signal S5 is transmitted by the system control circuit 4 upon receipt of the detected signal, and the recording is automatically stopped accordingly. By this method, the useless recording is discontinued.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic recording stop system in a magnetic recording/reproducing apparatus when no video signal is received.

[Conventional technology]

As a conventional device, for example, the book rNHK Home Video Technology, edited by Japan Broadcasting Corporation (April 20, 1980, 1st edition, November 10, 1980, 5th edition), pages 191 to 196 There are some listed. It states that if you want to continue recording while you go to bed or go out, the power will automatically turn off when recording is finished (sleeve function).

In addition, as described in Japanese Patent Application Laid-Open No. 57-8977, VT
It is known that when a channel is selected during R playback, the VTR is switched to a stop mode using the channel selection signal, thereby simplifying operation and preventing wasteful power consumption.

[Problem to be solved by the invention]

The conventional technology does not take into consideration the case where the video signal stops coming in during recording, and there is a problem in that wasteful recording continues.

SUMMARY OF THE INVENTION An object of the present invention is to automatically stop recording when no video signal comes in during recording, in order to prevent unnecessary recording from continuing.

[Means to solve the problem]

In order to achieve the above object, a video signal detection circuit is provided inside the magnetic recording and reproducing apparatus, and a function is added to send a signal to a system control circuit to automatically stop recording.

[Effect]

A video signal detection circuit provided in a magnetic recording/reproducing device detects when a video signal no longer comes in during recording and transmits a signal. Since the system control circuit receives the signal and automatically stops recording, there is no need to continue unnecessary recording.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

The figure is a system block diagram of one embodiment of the present invention.

When the magnetic recording/reproducing device is in the recording mode and a video signal is input to the video input terminal, the video signal detection circuit 1 does not operate and sends the video signal to the Y/C separation circuit 2 as it is. The Y/C separation circuit 2 converts the video signal into a luminance signal Y.
and a color signal C, and sends a luminance signal Y to a VSync separation circuit 3 and an emphasis circuit. Upon receiving the luminance signal Y, the YSync separation circuit 3 separates the vertical synchronization signal VSync from the luminance signal Y and sends it to the system control circuit 4.

However, when the video signal no longer enters the video input terminal, the video signal detection circuit 1 detects this.

The detection signal is transmitted to the system control circuit 4. The system control circuit 4 that has received the detection signal can send a control signal to automatically stop recording, thereby eliminating the need to continue unnecessary recording.

〔Effect of the invention〕

According to the present invention, when the magnetic recording/reproducing device receives a video signal and stops receiving it, recording is automatically stopped, so there is no need to leave wasteful recording on the magnetic tape, so the recording tape can be used effectively. I can do it.

[Brief explanation of drawings]

The figure is a system block diagram of one embodiment of the present invention. 1...Video signal detection circuit, 2...Y/C separation circuit. 3...VSync separation circuit・

Claims (1)

[Claims] 1. In a magnetic recording and reproducing device that records and reproduces input video signals by forming tracks on a magnetic tape using a rotating head, recording is automatically stopped when video signals no longer come in when in recording mode. A magnetic recording/reproducing device characterized by having additional functions.