JPS624954Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a recording/reproducing device for video signals such as a VTR, and is capable of modulating a reproduction signal and supplying the modulated signal from an output terminal to a preset tuner of a television receiver. In the playback device, tuning of the preset tuner is facilitated.

In conventional VTRs, the reproduced signal is generally modulated at the frequency of an empty channel of the television receiver, and the modulated reproduced signal is supplied to the tuner of the television receiver. In this case, modulators built into VTRs include those with a fixed carrier frequency and those with a steplessly variable frequency, while those with a built-in preset tuner are known as television receivers. A preset tuner consists of multiple tuning buttons arranged in the order of channel numbers on the front of the receiver, and multiple preset knobs attached to each button. In this case, a so-called ET tuner using a varicap is used. When using a preset tuner like this, first turn one preset knob while looking at the TV screen to adjust the screen for the desired station in the best condition, then adjust the other preset knobs. Make the same adjustments to complete the preset. After the preset is completed, by selectively pressing a channel selection button, it is possible to receive the broadcast station preset by the preset knob corresponding to the channel selection button. In this way, with the preset tuner, for example, the first channel of the receiver is used for broadcast station A, and the second channel is used for broadcast station B.
You can receive any broadcast station on any channel number on your receiver.

When connecting a VTR to a television receiver equipped with such a preset tuner and receiving the modulated playback signal, connect the preset tuner while applying the modulated playback signal to the input terminal of the receiver. For example, you need to turn the preset knob of an empty channel to adjust the screen to its best condition. In this case, the VTR is connected to the above input terminal.
When there is no signal from the controller, it becomes impossible to make adjustments.

Additionally, the preset tuner mentioned above is generally
A VTR is also equipped with a built-in preset tuner that records and reproduces the selected television signal, modulates the reproduced signal, and supplies it to the receiver. like this
When using a VTR, it is necessary to preset the tuner of the VTR and the tuner of the receiver before recording. To this end, the VTR is placed in E/E mode, whereby a signal detected from the output of the VTR's tuner is applied essentially directly to the modulator, and a modulated signal is applied to the receiver's preset tuner. I have to. In this E/E mode state
Tuning is done using the VTR's tuner and the receiver's tuner, but in this case it is extremely difficult to adjust the preset knobs on both to get the screen to the best possible condition. Especially in the case of the UHF band, adjustment becomes even more difficult because strictness is required.

To solve this problem, some VTR models have a built-in preset tuner with a built-in preset knob that lights up a lamp when a certain station is selected to indicate that the tuner has been tuned. I am trying to display it. Then, in this state, the received signal is recorded and reproduced, and this reproduced signal is modulated and applied to the receiver to tune the receiver. However, this method is very inconvenient because it is not possible to tell whether the VTR and receiver are correctly adjusted or whether there is distortion unless the received signal is recorded and then played back.

This idea was created in view of the above-mentioned circumstances.
When installing a test pattern signal generator in a recording/reproducing device such as a VTR and presetting the receiver,
A signal obtained by modulating the test pattern signal obtained from the test pattern signal generator is applied to the receiver.

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

In FIG. 1, during recording, a received signal selected by a preset tuner 2 in a VTR 1, or a signal from, for example, a television camera applied to a line input terminal 3, is selectively transmitted to the VTR 1 through contacts a or b of a switch 4. It is added to the recording circuit 5. In the video recording circuit 5, when the received signal is added, the received signal is subjected to video detection and then subjected to processing such as FM modulation of the Y signal and conversion of the chroma signal to a predetermined frequency. will be accomplished. Also, when a signal from a television camera is added, similar processing is performed directly. The output signal of the video recording circuit 5 is applied to the rotary head 7 through the contact a of the switch 6, thereby being recorded on the magnetic tape 8. During reproduction, the signal reproduced from the magnetic tape 8 by the rotary head 7 is applied to the video reproduction circuit 9 through the contact b of the switch 6. After the video reproduction circuit 9 performs predetermined processing such as FM demodulation and frequency conversion of the reproduction signal,
The output signal is amplitude-modulated by a modulator 11 through a contact a of a switch 10. The modulated signal is applied from the output terminal 12 to the built-in preset tuner 15 through the input terminal 14 of the receiver 13. Further, the E/E mode mentioned above is set by closing the switch 16. As a result, the signal obtained from switch 4 is transmitted to rotary head 7.
The signal is processed directly by the video recording circuit 5 and the video reproducing circuit 9 without going through the magnetic tape 8, and is modulated by the modulator 11.

The above configuration is conventionally known, but in the present invention, the VTR 1 is provided with a test pattern signal generator 17, and the test pattern signal from the signal generator 17 is applied to the modulator 11 through the contact b of the switch 10. That's what I do.

When performing preset adjustment of the tuner 15 of the receiver 13 with the above configuration, the switch 10 is closed to the contact b side. If the modulator 11 is of a variable type, it is fixed at an appropriate frequency. When the signal generator 17 is driven in this state, the test pattern signal is modulated by the modulator 11 through the switch 10, and the modulated test pattern signal is transmitted to the tuner 1.
Added to 5. Next, among the plurality of preset knobs on the tuner 15, for example, turn the preset knob that corresponds to an empty channel while looking at the television screen. The output signal of the tuner 15 is detected by a video detection circuit inside the receiver 13 and applied to the cathode ray tube. As a result, a black and white test pattern 19 vertically divided into two, for example, is displayed on the screen 18 as shown in FIG. By turning the preset knob until this test pattern 19 is in the best condition, a certain channel of the tuner 15 can be preset for the carrier frequency of the modulator 11. To perform playback in this state, switch the switch 10 to contact a side, and
Set VTR1 to playback mode. Furthermore, the user presses the channel selection button on the tuner 15 for the channel preset as described above. As a result, the signal reproduced from the tape 8 by the rotary head 7 is sent from the video reproducing circuit 9 through the switch 10, modulated by the modulator 11, and then applied to the internal video circuit of the receiver 13 through the preset channel of the tuner 15. . This allows the signals recorded on the magnetic tape 8 to be reproduced on a television screen.

Next, when preset adjustment of the tuner 2 of the VTR 1 is to be performed, the preset adjustment of the tuner 15 of the receiver 13 is first performed in the same manner as described above. Next, the switch 10 is switched to the contact a side, and the switch 16 is closed to set the VTR 1 to E/E mode. Next, turn one preset knob on tuner 2 to tune. As a result, when a certain broadcasting station is received, the received signal is modulated by the modulator 11 via the switch 4, the video recording circuit 5, the switch 16, the video reproducing circuit 9, and the switch 10. The modulated signal is applied to the video circuit through a preset channel of the tuner 15,
As a result, the image of that broadcasting station is displayed on the TV screen. Then, by turning the preset knob on the tuner 2 until the screen is in its best condition, the preset for that channel is completed.
Next, by sequentially making similar adjustments to the other preset knobs of the tuner 2, desired broadcast stations can be preset to each channel of the tuner 2, respectively.

Next, an embodiment of the test pattern signal generator 17 will be described with reference to FIG.

In FIG. 2, the signal generator 17 includes an oscillator 20, a monomulti 21, and an adder 22 in order to obtain the test pattern signal 19 shown in FIG. The oscillator 20 oscillates a rectangular wave signal 23 with an H period (horizontal scanning period) as shown in FIG. 4A. The monomulti 21 is triggered by the fall of the rectangular wave signal 23, and outputs a negative pulse signal 24 having a pulse width of, for example, 5 μsec as shown in FIG. 4B. As a result of combining the rectangular wave signal 23 and the pulse signal 24 in the adder 22, a test pattern signal 25 as shown in FIG. 4C is obtained from the adder 22. The pulse signal 24 in this signal 25 serves as a horizontal synchronization signal. This signal is modulated by a modulator 11 through a switch 10, and then applied to a receiver 13, resulting in a test pattern 1 shown in FIG.
You can get 9. In this case, since the test pattern 19 is a pattern obtained by vertically dividing the screen 18 into two, it is possible to display a sufficiently stable test pattern 19 using only the horizontal synchronization signal without inserting a vertical synchronization signal into the signal 25. Can be done. still,
A burst signal may be inserted into the test pattern signal 25 if necessary. Further, instead of the oscillator 20, various other oscillators built in the VTR 1 may be used. For example, 60-70K on the erase head
A bias oscillator for supplying an erase current of approximately Hz, a signal obtained by dividing the output of a chroma signal subcarrier oscillator, etc. can be used. Furthermore, since there is a possibility that the tuner 15 of the receiver 13 receives the image wave and tunes it, an audio test signal generator is further provided.
If adjustment is made in conjunction with step 7, tuning can be done more accurately.

The present invention provides video signal recording and reproducing means 5, 7, 9.
, a test pattern signal generator 17, and a switch 10 for selecting either one of the video signal obtained from the recording/reproducing means and the test pattern signal obtained from the test pattern signal generator.
and a modulator 11 to which the video signal or test pattern signal selected by the switch is supplied.
The modulated video signal or modulated test pattern signal obtained from the modulator is supplied to the preset tuner 15 of the television receiver 13.
The present invention relates to a recording/reproducing apparatus which is equipped with an output terminal 12 connected to the preset tuner, and in which the test pattern signal is selected by the switch when adjusting the preset tuner.

Therefore, according to the present invention, when a recording and reproducing device is connected to a television receiver equipped with a preset tuner and the tuner is tuned, the adjustment can be performed even when there is no reproduction signal from the recording and reproducing device. Can be done. Further, even if the recording/reproducing apparatus is provided with a preset tuner, tuning can be easily performed between the tuner of the recording/reproducing apparatus and the tuner of the receiver.

[Brief explanation of the drawing]

Fig. 1 is a circuit system diagram showing an embodiment of the present invention, Fig. 2 is a circuit system diagram showing an embodiment of a test pattern signal generator, Fig. 3 is a diagram showing an example of a test pattern signal, and Fig. 4A. , B, and C are waveform diagrams of each part in FIG. 2. In addition, in the symbols used in the drawings, 1...
...VTR, 5...Video recording circuit, 7...Rotary head, 8...Magnetic tape, 9...Video playback circuit, 1
1... Modulator, 13... Receiver, 15... Preset tuner, 17... Test pattern signal generator, 19... Test pattern, 25... Test pattern signal.

Claims (1)

[Claims for Utility Model Registration] Video signal recording and reproducing means; a test pattern signal generator; and any of the video signal obtained from the recording and reproducing means and the test pattern signal obtained from the test pattern signal generator. a modulator to which the video signal or the test pattern signal selected by the switch is supplied; and a modulated video signal or the modulated test pattern signal obtained from the modulator. and an output terminal connected to a preset tuner of a television receiver, wherein the test pattern signal is selected by the switch when adjusting the preset tuner.