KR900008902Y1 - Audio editing circuit using double deck vtr - Google Patents

Abstract

No content.

Description

Audio editing circuit using double deck VTR

1 is a block diagram showing an embodiment of the present invention.

2 is a detailed electrical diagram of FIG.

* Explanation of symbols for main parts of the drawings

10: logic unit 20: muting control unit

30: external audio input unit 40: switch

The present invention relates to an audio editing circuit using a double deck TVR, and more particularly, to provide a circuit capable of dubbing an external audio signal.

In general, only VHS standard (12.65mm) video tape can be used for VHS type VTR, and only 8mm video tape can be used for 8mm type VTR. In the VHS mode, you can record from the B deck (8mm) or from the B deck to the A deck so that you can edit the video tape.

However, in the conventional double deck video system, an external audio signal cannot be recorded and edited at the time of recording.

Accordingly, an object of the present invention is to provide a circuit that can edit an external audio signal when recording a video signal, and mix an external audio signal when recording a video tape, in order to solve the above-mentioned drawback. There is.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Applying a recording signal (S ₅₎ of the external input signal (S₁) and A deck of playing signal (S₂) and B deck recording signal (S₃) and B deck play signal (S₄) and A deck of the A deck and B The logic unit 10 for outputting a control signal by recognizing the recording operation between the decks is a circuit composed of logic gates (G₁-G₄), and the A deck and the B deck between the decks in accordance with the output signal of the logic unit 10. The muting control unit 20 outputs a control signal for muting the audio signal transmitted during recording, and mixes and records an external audio signal by the dubbing control signal S6. The resistors R'-R9 and the transistors Q'-Q ₅ ) is a circuit composed of an external audio input unit 30 for applying an external audio signal S ₇ to an audio transmission line of A deck or B deck through the switch 40 according to the output signal of the muting control unit 20. Is a circuit composed of a capacitor (C₁), a resistor (R ₁₀ -R ₁₃ ), and a transistor (Q6). Roy.

In addition, the switch 40 is a switch for selectively applying an external audio signal input to the A deck or the B deck according to the switching.

First, when deck A is played and deck B is recording, to edit the external audio signal to the video tape being recorded, the external input signal (S₁), the play signal of A deck (S₂) and the recording signal of deck B (S₃) Are all applied to the logic section 10 as a logic " 1 " (high level) signal.

The logic " 1 " signal appearing at the output terminal of the AND gate G₁ to which the S2 signal and the S₃ signal are applied are input to the AND gate G₄ together with the logic " 1 "

At this time, the logic " 1 " signal shown at the output terminal of the AND gate G 'conducts the transistor Q' through the resistor R ', and accordingly, the transistor Q2 is continuously connected to the emitter of the transistor Q2. The applied power source B ⁺ is applied to the bases of the transistors Q 3 and Q 연결된 connected to the audio signal input / output lines of the decks A and B through the collectors so as to conduct both.

Therefore, as the muting transistors Q3 and Q 'are turned on, the audio signal output from the deck A in the fleece is muted so that it is not applied to the deck B in recording.

On the other hand, the power (B ⁺ ) signal shown in the collector of the transistor Q₂ is divided by the resistors R ₁₀ and R ₁₁ and applied to the base of the transistor Q ₆ to conduct the external input audio signal S. ₇ ) is applied to the audio input terminal IN of the B deck being recorded through the conducting transistor Q ₆ and the switch 40.

When the dubbing signal S ₆ of logic " 1 " is input, the collector signal of the transistor Q2 applied to the muting transistors Q3 and Q 'of decks A and B is supplied to the transistors Q3 and Q'. The muting control signal flows to ground because the transistor Q ₅ is conducted so that it is not applied.

Therefore, the output audio signal of the deck A is not muted and mixed with the external audio signal S ₇ applied through the switch 40 to be input to the deck B and dubbed.

As described above, according to the present invention, when the video tape is edited using the double deck VTR, the external external signal can be dubbed, thereby increasing the function of the double deck system, thereby contributing to the improvement of the product power.

Claims (1)

In the double-deck VTR that can record each other by integrating the VHS method and the 8mm method, the recording operation between the two decks can be performed by applying the external input signal (S₁) and the recording or play signal (S₂-S₄) of the two decks. The logic unit 10 which recognizes and outputs a control signal and the audio signal transmitted between the two decks according to the logic level of the output signal of the logic unit 10 and mute control by the dubbing signal S ₆ . The muting control unit 20 to prevent the muting by grounding the signal, and the external input audio signal S ₇ is input to the deck being recorded through the recording selection switch 40 according to the output signal of the muting control unit 20. Audio editing circuit using a double deck VTR, characterized in that it comprises an external audio input unit 30.