JP2658688B2 - Magnetic recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus provided with a non-linear aperture circuit which varies an aperture amount according to the performance of a recording medium.

[0002]

2. Description of the Related Art FIG. 2 is a block diagram showing a configuration of a magnetic recording / reproducing apparatus for determining the performance of a magnetic recording medium. 2 is a video signal input terminal. The video signal input to the video signal input terminal 1 is fixed to a fixed level by an AGC (automatic gain control) circuit 2.
The output signal of the AGC circuit 2 is input to the Y / C separation circuit 3.

The Y / C separation circuit 3 separates a video signal into a luminance signal and a chrominance signal, and the chrominance signal is sent to a chrominance signal processing circuit 9. The luminance signal is sent to the low-pass filter 4. The low-pass filter 4 limits the band of the luminance signal. The output signal of the low-pass filter 4 is sent to a clamp circuit 5.

The clamp circuit 5 receives the output signal of the low-pass filter 4, fixes the luminance signal at an arbitrary potential, and sends the output signal to the pre-emphasis circuit 6. This pre-emphasis circuit 6 emphasizes high frequencies. The output signal of the pre-emphasis circuit 6 is sent to the clip circuit 7. The clipping circuit 7 cuts off the spike voltage generated in the pre-emphasis circuit 6 at an arbitrary level. The output signal of the clipping circuit 7 is sent to the FM modulation circuit 8.

The FM modulation circuit 8 frequency-modulates the luminance signal and sends the output signal to the mixing circuit 10. An output signal from the color signal processing circuit 9 is also input to the mixing circuit 10. The color signal processing circuit 9 performs low-frequency conversion of the color signal, and a mixing circuit (hereinafter, referred to as a MIX circuit) 10 mixes the output signal of the color signal processing circuit 9 and the output signal of the FM modulation circuit 8 to record. The signal is output to the amplifier 11.

The recording amplifier 11 has a frequency characteristic,
The output signal of the X circuit 10 is amplified and output to the video head 12. The video head 12 records the output signal of the recording amplifier 12 on the recording medium 13 and
The video signal recorded on the recording medium 13 is reproduced.

The reproduction signal reproduced by the video head 12 is amplified by a reproduction amplifier 14 and then subjected to envelope detection by an envelope detection circuit 15 to convert the reproduction envelope into a voltage. Envelope detection circuit 15
Is sent to the discrimination microcomputer 16. The determination microcomputer 16 determines the performance of the recording medium 13 based on the detection output of the envelope detection circuit 15 and controls the pre-emphasis circuit 6, the FM modulation circuit 8, and the recording amplifier 11.

Next, the operation will be described. The video signal input to the video signal input terminal 1 is fixed at a fixed level by the AGC circuit 2, separated into a luminance signal and a chrominance signal by the Y / C separation circuit 3, and the chrominance signal is sent to the chrominance signal processing circuit 9. The luminance signal is band-limited by the low-pass filter 4, the luminance signal is fixed at an arbitrary potential by the clamp circuit 5, and is sent to the pre-emphasis circuit 6.

The pre-emphasis circuit 6 emphasizes the high frequency range of the luminance signal and sends an output signal to the clip circuit 7. The clip circuit 7 cuts the spike voltage generated in the pre-emphasis circuit 6 at an arbitrary level. , FM modulation circuit 8. In the FM modulation circuit 8, the luminance signal is frequency-modulated and output to the MIX circuit 10.

On the other hand, the color signal is low-frequency converted by the color signal processing circuit 9, and the output signal of the color signal processing circuit 9 is sent to the MIX circuit 10. The MIX circuit 10 is a color signal processing circuit 9
And the output signal of the FM modulation circuit 8 are mixed and output to the recording amplifier 11. The recording amplifier 11 amplifies the output signal of the MIX circuit 10 and outputs the amplified signal to the head 12, and the head 12 records a video signal on the recording medium 13.

Next, an operation for determining the performance of the recording medium 13 will be described. Under the control of the discrimination microcomputer 16, the FM modulation circuit 8 outputs a sine wave of an arbitrary frequency, and this sine wave is sent to the head 12 (video head) via the MIX circuit 10 and the recording amplifier 11, and this head 12 Is recorded on the recording medium 13.

The video signal recorded on the recording medium 13 is reproduced by the head 12, and the reproduced signal is amplified by the reproduction amplifier 14, and the reproduced envelope is converted into a voltage by the envelope detection circuit 15. Output.

When the voltage outputted from the envelope detection circuit 15 becomes higher than an arbitrary value, the discrimination microcomputer 16 judges that the recording medium has good performance, and when recording an actual video signal, the discrimination microcomputer 16
The pre-emphasis circuit 6 emphasizes the higher frequency range than usual, and the recording amplifier 11 emphasizes the lower frequency range than usual to record. In this way, a high-performance medium has higher image quality than usual.

[0014]

Since the conventional magnetic recording / reproducing apparatus is configured as described above, the frequency characteristics of the pre-emphasis circuit 6 and the recording amplifier 11 are standardized by the VHS standard, and the variable range Less is. Further, if the characteristics of the pre-emphasis circuit 6 and the recording amplifier 11 are varied, there is no margin for the inversion phenomenon, and the inversion phenomenon may occur or the sound quality may deteriorate. Japanese Patent Application Laid-Open No. 2-288790 is an approximate technique.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has a wide image quality variable range and magnetic recording capable of performing recording based on the performance of a recording medium without causing inversion and sound quality deterioration. It is intended to obtain a playback device.

[0016]

SUMMARY OF THE INVENTION The magnetic recording reproducing apparatus according to the present invention comprises a non-linear aperture means varying the aperture amount nonlinear according to the luminance signal input,
Mixing the FM modulating means for frequency modulating said luminance signal, a color signal processing means for low-frequency converting a color signal and an output signal of the output signal of the color signal processing means <br/> said FM modulation means
Signal mixing means for generating a signal containing an arbitrary frequency component
A signal generating means that, at the time of the actual video signal recording said signal
Amplifies the output signal of the No. mixing means, and a signal amplifying means for amplifying an output signal of rehearsal recording and sometimes the signal generating means for performance determination of the recording medium, or the signal amplifying means
La of the output signal is recorded on the recording medium, and a recording and reproducing means for outputting a reproduction signal by reproducing the recording medium, the output of the signal generating means instead of the output signal of said signal mixing means during the rehearsal recording causes recorded on the recording medium a signal through said signal amplifying means and said recording and reproducing means, an output signal from said signal generating means recorded on the recording medium when playing by the recording and reproducing means <br / > If the reproduced signal voltage is above a predetermined level, the image of the actual
When recording a signal, according to the input luminance signal,
Non- linear aperture means
It is obtained by a control means for controlling to increase the near.

[0017]

According to the present invention, the signal from the signal generating means is provided.
And it was recorded in a record medium and reproducing the recorded signal
If reproduction signal voltage can have on a given level than non-linear when recording video signals of the actual, an aperture amount of <br/> nonlinear aperture means according to the luminance signal input
For recording to increase and a recording medium on.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the magnetic recording / reproducing apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of one embodiment. 1. In FIG. 1, in describing the configuration, the same parts as in FIG. 2 will be assigned the same reference numerals only in order to avoid redundant description, and parts different from FIG. 2 will be mainly described.

As is clear from the comparison of FIG. 1 with FIG. 2, a new processing system for the luminance signal is provided between the output side of the low-pass filter 4 and the input side of the clamp circuit 5 in the configuration of FIG. A non-linear aperture circuit 19 is inserted.

A switch means 18 is inserted between the output side of the MIX circuit 10 and the input side of the recording amplifier 11. The switch means 18 switches between the output signal of the MIX circuit 10 and the output signal of the sine wave oscillator 17 under the control of the discrimination microcomputer 16 and sends it to the recording amplifier 11.

The sine wave oscillator 17 outputs a sine wave of an arbitrary frequency. When performing rehearsal recording on the recording medium 13 to determine the performance of the recording medium 13, the output signal of the sine wave oscillator 17 is The data is sent to the recording amplifier 11 through the switch means 18.

Further, when the non-linear aperture circuit 19 actually records a video signal on the recording medium 13, the aperture amount is controlled by the control of the discrimination microcomputer 16 according to the performance of the recording medium. .
Note that the FM modulation circuit 8 is not controlled by the output signal of the discrimination microcomputer 16 in FIG. Other configurations are the same as those in FIG.

Next, the operation of the embodiment of the present invention will be described. In order to determine the performance of the recording medium 13, the switch means 18 is switched by the determination microcomputer 16 to output the output signal of the sine wave oscillator 17 oscillating at an arbitrary frequency to the recording amplifier 11.
1 amplifies the output signal of the sine wave oscillator 17 and
2 and the head 12 records a sine wave on the recording medium 13.

The sine wave recorded on the recording medium 13 is reproduced by the head 12, and the reproduced signal is amplified by the reproduction amplifier 14 and sent to the envelope detection circuit 15. The envelope detection circuit 15 converts the reproduced envelope into a voltage and inputs the voltage to a discrimination microcomputer 16.

When the voltage input from the envelope detection circuit 15 exceeds an arbitrary value, the determination microcomputer 16 determines that the recording medium 13 is a recording medium having good performance. When a video signal is recorded on the recording medium 13 determined to be good, recording using the output signal of the sine wave oscillator 17, that is, recording medium 1 based on rehearsal recording
Based on the performance determination result of No. 3, the aperture amount of the non-linear aperture circuit 19 is variably recorded.

In this case, with a recording medium having good performance, high image quality can be obtained by recording with an increased aperture amount.

[0027]

As described above, according to the present invention, it is possible to provide a non-linear aperture means in a luminance signal processing system and to generate a signal including an arbitrary frequency component.
The output signal from the means is recorded on a recording medium and the reproduced output is recorded.
If There above value at the time of recording of the video signal of the actual, ON
Since to increase the aperture amount of the non-linear aperture means nonlinearly according to the luminance signal force, without causing the inversion phenomenon and sound quality, tolerance is large in the image quality adjustment, based on the performance of the recording medium recording , And an effect of obtaining high image quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a magnetic recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a conventional magnetic recording / reproducing apparatus.

[Explanation of symbols]

 Reference Signs List 1 video signal input terminal 3 Y / C separation circuit 8 FM modulation circuit 9 color signal processing circuit 10 mixing (MIX) circuit 11 recording amplifier 12 head 13 recording medium 14 reproduction amplifier 15 envelope detection circuit 16 discriminating microcomputer 17 sine wave oscillator 18 Switch means 19 Non-linear aperture circuit

Claims (1)

(57) [Claims] (1)InputLuminance signalIn response to theaperture
The amountNon-linearVariable nonlinear aperturemeans
And FM modulation for frequency-modulating the luminance signalmeansAnd color signal processing for low-frequency conversion of color signalsmeansAnd this color signal processingmeansOutput signal and FM modulationmeansOut of
Mix with force signalsignalmixturemeansAnd any frequencySignal generating means for generating a signal including a component
When recording the actual video signal,signalmixturemeansOutput signal
Rehearser for amplifying the signal and determining the performance of the recording medium
LeRecordSometimes saidSignal generation meansThe output signal ofFaith
Signal amplificationMeans and thisSignal amplificationmeansFromIs output to the recording medium.
And reproduces the recording medium to output a reproduction signal.Record
Recording and playback meansAt the time of the rehearsal recordingsignalmixturemeansOutput signal
Instead,Signal generation meansThe output signal ofSignal amplificationmeans
And saidRecording and playbackRecording on the recording medium through the means
And recorded on the recording mediumSignal generationOutput from the means
SignalRecording and playbackPlay by meansWhenPlayback signal
If the voltage is higher than the specified levelIf theImage of the edgeSignalRecord
RecordDoTimeIn accordance with the input luminance signal,Said non
The aperture amount of the linear aperture meansNon-linear increase
Control means for easy controlWithCharacterized by
ToMagnetic recording and reproducing device.