JPS6275901A - Copy prohibiting device for recording and reproducing device - Google Patents

Abstract

PURPOSE:To execute the copy prohibiting in the double deck type compound type recording and reproducing device which can easily dub by detecting the coincidence of respective recording signal and reproducing signal of one side driving mechanism and other side driving mechanism and interrupting the recording action. CONSTITUTION:One side reproducing signal through a rotating head 117 for a recording and reproducing driving mechanism 100 of a VTR, etc., a luminance signal reproducing system 118 and a synchronizing separator circuit 5, and other side recording signal through a luminance signal recording system 215 of a recording and reproducing driving mechanism 200 of the VTR, and a synchronizing separator circuit 6 are supplied to an AND gate 7 of the coincidence detecting circuit. In accordance with the coincident output from the gate 7 through a control signal generating circuit 8 a transistor 9 of the mechanism 200 is turned off, and the electric power source voltage to the recording system 215 is interrupted and the recording in the mechanism 200 is prevented. Consequently, the copy in the double deck type or the compound type recording and reproducing device, which can dub, can be prohibited without fail.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a circuit configuration in which the recording function of a so-called double cassette or double deck tape recorder or video tape recorder can be restricted according to conditions. This is related.

2. Description of the Related Art An audio tape recorder called a double deck or double cassette is equipped with a drive groove into which two tape cassettes are attached, each for recording and playback.

Therefore, with this type of device, one driver can be operated to listen to the reproduced sound while the other driver can be operated at the same time to record the sound, or the earphones can be used to listen to the reproduced sound. It's very convenient because you can enjoy it.

A similar device is still being considered for video tape recorders, and as production costs continue to fall, demand will increase and it is likely that they will appear on the market in the future.

Problems to be Solved by the Invention A product in which the recording and playback functions are independent and integrated into the cabinet will facilitate dubbing between tapes, which is convenient, but may pose social problems. cause. In general, the content recorded on magnetic tape is music or video, and many of these are copyrighted works created by humans.

Therefore, there is a great deal of dissatisfaction from copyright holders regarding the sale of this type of device that allows copying of copyrighted works indiscriminately. In order to eliminate such social problems, it is necessary to make it possible for products such as double decks to allow dubbing within the same device.

Means for Solving the Problems The present invention has at least one side having a function of performing a recording operation,
This invention is applied to a magnetic recording/reproducing device having a pair of drive grooves, the other of which has the function of performing a reproducing operation. The present invention has a detection means, and compares the recording input signal component of one drive groove performing a recording operation with the reproduction output signal component of the other drive groove undergoing a reproduction operation, and detects whether the two components match. I am trying to detect it. Further, the present invention further includes a control means, and receives a detection output indicating consistency from the detection means and operates to prevent the operation of one of the drive grooves.

According to the present invention, in a device such as a double cassette deck that has a playback mechanism and a recording mechanism as a pair and can operate simultaneously, it is possible to prevent signals from these playback mechanisms from being recorded by the paired recording mechanism. . Further, in this case, since the consistency between the reproduced output and recording input signals is detected, it is sufficient to handle the same type of signals, and the detection means can have a simple configuration.

Example Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block circuit diagram of an embodiment of the magnetic recording/reproducing apparatus of the present invention.

In the figure, reference numerals 100 and 200 are respectively the same type of drive grooves, namely V l'' I(, decks).

Therefore, the corresponding parts in both are shown with the I-th and second-digit numbers being the same, and only one will be explained.

1 is an antenna input terminal, and 2 is a tuner.

The video output of Team 2 and the signal input to the video input terminal 11 from other video equipment are connected to the input selection switch 11.
3 to be selected.

The signal selected by switch 113 is applied to luminance signal recording system and color signal reproducing system circuits 11.5, 116, converted into a recording signal, transmitted to rotary head system 117, and recorded on a magnetic tape. Out of the outputs of tuner 2, audio output 1 is similarly selected by a signal from external input terminal 112 and switch 114. The selected audio signal is converted into a recording signal through an audio signal recording system circuit 121, and is recorded on a magnetic tape by an audio head 122.

Luminance signal reproduction system circuit 118 and color signal reproduction system circuit 11
Reference numeral 9 converts and demodulates the RF multiplied signal brightness signal and color signal taken out by the rotary head system 117, and synthesizes a color composite video signal. On the other hand, the signal picked up from the audio head 122 is extracted as an audio signal by an audio signal reproduction system circuit 123. The color composite video signal and audio signal can be taken out from output terminals 120, 124, and switches 1.0. RF by II
The signal is supplied to converter 3. The RF converter 3 modulates the broadcast carrier wave of the television 2 or channel by using the input signal ρl, and outputs the output signal from the output terminal 4. Up to this point, the circuit arrangement has been well-known, but next, a control system inserted into the system of the present invention will be explained.

A part of the reproduced video signal of the luminance signal reproduction system circuit 118 is applied to the synchronization separation circuit 5, and a horizontal synchronization signal is taken out as an output thereof and applied to one input terminal of the AND gate 7. 6 is a similar synchronization separation circuit, which is connected to separate the horizontal synchronization signal from the video signal that is input to the luminance signal recording system circuit 2150 of the other drive system 200 and apply it to the other input terminal of the AND gate 7. There is. The output of the AND gate 7 is given to a control signal generation circuit 8 such as a retriggerable multivibrator, which generates a control signal according to the input state as described later, and outputs it to the output stage side of the luminance signal recording system circuit 215. They are arranged so as to apply the supplied power source voltage to a switching transistor 9 for on/off control.

A connection similar to that of the control system described above is made in the luminance signal reproduction system circuit 21.
8 and the luminance signal recording system 116, but the explanation will be omitted since it would be redundant.

In the circuit shown in FIG. 1, it is assumed that the drive system 100 is placed in the reproducing operation mode, and at the same time, the drive system 100 is placed in the recording mode. Further, the output signals of the output terminals 120 and 124 are applied to the input terminals 211 and 212, respectively, and the switches 213 and 214 send those signals to the recording system circuit 21.
5, 216, and 221 for dubbing. In this case, horizontal synchronization signals of the same phase are obtained from the synchronization separators 5 and 6, and a synchronization pulse is output from the AND gate 7.

This synchronization pulse is applied to the control signal generator 8, which outputs a negative DC voltage as a control signal. This control signal is applied to the switching transistor 9 to cut off the power supply voltage applied to the output stage of the luminance signal recording system circuit 215. Therefore, the video signal is cut from the signal applied to the rotary head system 217, making the recording operation unsatisfactory.

Further, the drive system 100 is in the regeneration operation mode, and the drive system 2
Even if 00 is in the recording operation mode, the recording system circuit 215,
Consider a case where the input signals given to 216 and 221 are not the output of the drive system 100. At this time, since the horizontal synchronization signals obtained from the synchronization separation circuits 5 and 6 are out of phase, the output of the AND gate 7 becomes a low level and does not change. Therefore, the output of the control signal generator 8 becomes a positive DC voltage, which causes the transistor 9 to turn on and apply a power supply voltage to the luminance signal recording system 215 to perform a normal recording operation.

In the arrangement shown in FIG. 1, the synchronization separation circuits 5, 6 and the AND gate 7 constitute a detection means for comparing the recording input signal component and the reproduction output signal component and detecting the identity of both components. The signal generating circuit 8 and the switching transistor 9 constitute a control means for restricting the recording operation to prevent it. Various other types of detection means and control means can be considered. As a detection means, it is also possible to detect the consistency of amplitude in addition to the phase. For example, it is possible to compare the reproduction output signal component and the recording input signal component using a differential amplifier, and to extract the output of the difference by applying it to a low-pass filter. . The control means includes means for turning on and off a noise signal generator to mix it into the recording signal, means for changing the frequency of a reference oscillator of the recording system, means for stopping a mechanical drive groove, and the like.

Effects of the Invention As described above, according to the configuration of the present invention, it is possible to prevent dubbing that violates the rules of copyright law in a double-deck VTR/audio tape recorder. In this case, the present invention can be similarly applied to a double deck that incorporates decks of different types of VTR systems, and can also be applied to a composite device that combines a disk player and a tape deck.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram of a magnetic recording/reproducing apparatus according to an embodiment of the present invention. 100 and 200...recording/reproduction drive groove, 5 and 6...synchronization separation circuit which is a component of the detection means, 7.
. . . AND gate that is a part of the detection means; 8 . . . a control signal generation circuit that is a part of the control means; 9 . . . a switching transistor that is a part of the control means.

Claims (1)

[Claims] In a recording/reproducing device having a pair of drive mechanisms, at least one of which has a function of performing a recording operation and the other of which has a function of performing a reproduction operation, a recording input signal component of the one drive mechanism groove and reproduction of the other drive mechanism. a detection means for comparing the output signal components and detecting the coincidence of both components; and a control means for restricting the recording operation of the one drive mechanism in response to the detection output indicating the coincidence of the two components. A copy prohibition device for a recording/reproducing device, characterized by comprising: