JPS6047587A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To process a skew correcting signal and a head switching pulse logically and control switches, and obtain a normal signal in slow reproduction by providing the 1st and the 2nd delay lines and the 1st and the 2nd switches, and detecting the skew of the sum signal of a luminance and a color signal. CONSTITUTION:Two heads L1 and L2 having the same azimuth are arranged at a specific leading or lagging angle to a division of 180 deg., and luminance signals and color signals of reproducing signals of the two heads L1 and L2 are demodulated by a Y signal demodulator 3 and a C signal demodulator 4. The color signal is applied to the 1H delay line 5 and a switch 6 selects the 1H- delayed chromaticity signal or undelayed chromaticity signal to add the selected signal to the luminance signal at an addition point 16. This sum reproducing signal is applied to a 0.5H delay line 7, and a switch 8 selects the reproducing signal or delayed reproducing signal. The switch 8 is controlled with the output of a jumping circuit 10 to detect the skew of the sum signal, and the switch 6 is controlled by the output of a logical circuit 13 to output a normal signal in slow reproduction.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording/reproducing device having a helical skillet and a field-sdell function.

Conventional structure and problems Conventionally, tape formats that do not satisfy horizontal synchronization conditions, such as ■1-IS PAI-, SEC△M long-time format (8-hour recording mode), have field sprue and slow playback. The video signal at the time has skew distortion and the color order is disordered, so it is not a regular PAL signal,
Currently, it is not possible to use it as a SECAM signal.

OBJECTS OF THE INVENTION The present invention provides a magnetic recording and reproducing apparatus which can produce regular signals without skew distortion and color permutation during playback, even with tape formats that do not satisfy horizontal synchronization conditions. The purpose is to provide

Structure of the Invention The magnetic recording/reproducing device of the present invention has two
The heads are arranged at a predetermined lead angle or delay angle with respect to the index of 1800, and the luminance signal demodulation and chromaticity signal demodulation are performed from the reproduced signals by these two heads, and the chromaticity signal or this chromaticity is A first switch selects one of the signals delayed by 111 and adds it to the pox signal 8, and a second switch selects either this added signal or a signal delayed 0.5H to this added signal. The second switch performs switching by detecting the presence or absence of a skew signal in the addition signal, and the first switch performs switching based on a signal obtained by logically processing the skew correction signal and the head switching pulse. It is characterized by being configured to execute.

Description of examples An embodiment of the present invention will be explained below based on the drawings-3- do.

FIGS. 1a and 1b are diagrams showing examples of head specifications when performing field-to-sdell and slow playback, respectively. Arrow A represents the direction of cylinder rotation.

R1 and L-1 are normal recording and reproducing heads, and in the case of a, head L2 is arranged close to head R1 at an advance angle α, and during field still and slow playback, head 1-
1 and 12 are used. In FIG. 1, the letters R and L represent cases in which the direction of azimuth inclination is to the right and to the left, respectively. Further, α is selected to be 2.2511, which is the period of the horizontal synchronizing signal of the television system.

Figure 2 shows the head trajectory during field still playback.
0 This pattern indicates that the horizontal synchronization misalignment with the adjacent rack is 025H, which also indicates the color arrangement state of the PAI- signal and SECAM signal. This shows a long format pattern in the VH8 standard.

FIG. 3 shows head L1 of FIG. 1a. 1-2 shows the configuration of a circuit that processes a reproduced signal obtained by tracing the locus of FIG. 2. Head L1. The L2 signals are each amplified via amplifiers 1.2, the Y signal is demodulated by the luminance signal demodulator 3, and the chromaticity signal 1! In the iI tone circuit 4, C(i
The signal is demodulated. The C signal output from the chromaticity signal lI tone circuit 4 is output via the 1H delay line 5 or by bypassing the 1[1 delay line 5. The switch 6 is selected, and the output signal of the switch 6 is added to the output signal of the luminance signal 4I modulator 3 at the addition point 16 and output. The output signal of summing point 16 is output via 0.5 day delay line 7 or by bypassing 0.51-IN if rA7. Switch 8 is the selected switch. The 0.511 delay 1i17 is for correcting the continuity of the period of the horizontal synchronizing signal during still operation, and performs skew correction. PAL signals and SECAM signals are transmitted using a kind of line sequential method, and B-Y, R-
If the permutation of Y is disrupted, color reproduction on the television screen will become unstable. The 1H delay line 5 is for correcting the above-mentioned color permutation of the color aperture during still reproduction.

-5- Note that the switch 6.8 is switched as follows. The jumping circuit 10 detects a skew component of 0.5H from the signal at the adding point 16 via the horizontal separation circuit 9, controls the switch 8, and performs misskew correction. On the other hand, the output signal of the jumping circuit 10 (Fig. 4a)
is input to the logic circuit 13 via the integrating circuit 11 and the waveform shaping circuit 12, with jitter components removed. This logic circuit 13 inputs the output signal of the waveform shaping circuit 12 (Fig. 4b) and the head switching pulse (Fig. 4C), performs logical processing, outputs the signal shown in Fig. 4d, and performs color permutation. The switch 6 is controlled to correct the signal d.The signal d repeats eight fields of the head switching pulse C as one cycle.

By switching the switch 6.8 in this manner, the reproduced video output of the switch 8 output becomes a normal signal without the problem of skewed color permutation.

Incidentally, during fine-slow playback, a door-in-slow start signal @e is further input, and the logic circuit 13 generates a signal d. In this case, the signal from the jumping circuit -0-10 is also input to the logic circuit 13 at the same time. Figure 5 shows the relationship between these signals, and the lowest period of the fine slow start signal e is the periodicity (10
Field minutes) What's going on? Signal d' is the waveform obtained when the head is switched from L2 to R1 for one field in order to improve the drop in the instantaneous envelope of the track movement caused by the tape movement during slow playback. shows.

In the above embodiment, the head L2 was arranged at an advance angle α of 2.251-1 with respect to the head R1, but this advance angle α is not limited to 2.25H;
n -1-0,25) R1 However, n may be an integer of 0.1.2°3, . . . . Further, the head L2 may be arranged with a delay angle β of 1.7511 with respect to the head R1 as shown in FIG. Furthermore, this delay angle β is (2n
-0,25) can be expressed as l-1.

In the above embodiment, the normal recording and reproducing head [2 was used for special reproduction, but it is also possible to provide two heads for special reproduction separately from heads L1 and L2, and to have a 4-7-rad configuration. Just special re/l- head L+
, the mounting angle of L-2 is α for the index of 1800
, β.

In the above embodiment, the left azimuth head L2 was added for special reproduction, but in this case, the right azimuth head R2 is disposed close to the head L1 at an advance angle α or a delay angle β, and is connected to the head R1. Still by combination of R2. A similar effect can be obtained by performing slow playback.

According to the detailed description of the invention, the magnetic recording book/apparatus of the present invention includes:
The video output signal during field still and slow playback is a regular PAL without skew distortion and color permutation disorder.
signal or SFCAM signal.

The heads 11 and 12 can also use a pattern that satisfies the 1'' alignment condition, for example, the E''A1-signal of the Vl-IS standard mark tII-■ hood, and the SECAM bow with closed eyes. In this case, the gap 1-correction is 0.2
511 delay line is required.

-8-

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, FIG. 1a, 1) is a cylinder configuration diagram showing the head specifications, and FIG.
A pattern diagram during still playback in S standard long-time formats 1~, Figure 3 is a configuration diagram of the reproduced signal M processing circuit, Figures 4 and 5 are the still of Figure 3, and during slow playback, respectively. It is a waveform diagram of each part. Ll. l-2... Head, 3... Bright spot signal demodulator,
4... Chromaticity signal demodulator, 5... 1 day delay line, 6...
・Switch [first switch], 7... 0.5H delay line, 8... switch [second switch], 9... horizontal separation circuit, 10... jumping circuit, 11...
Integrating circuit, 12... Waveform shaping circuit, 13... Logic circuit, C... Head switching pulse agent Yoshihiro Morimoto 01 Figure 1 Figure 3 ε 528- Figure 4

Claims (1)

[Claims] 1. Two heads with the same azimuth
The luminance signal demodulation and the chromaticity signal are demodulated from the reproduced signals from these two heads, and the chromaticity signal or this chromaticity signal is
A first switch selects one of the H delayed signals and adds it to the prepaid luminance signal, and a second switch selects and outputs either this added signal or a signal delayed by 0.5 H. The second switch detects the presence or absence of skew in the addition signal and executes the switching, and the first switch detects the presence or absence of skew in the addition signal, and the first switch detects the presence or absence of skew in the addition signal, and the first switch detects the presence or absence of skew in the addition signal, and the first switch detects the presence or absence of skew in the addition signal, and the first switch detects the presence or absence of skew in the addition signal and executes the switching, and the first switch detects the presence or absence of skew in the addition signal and executes switching, and the first switch detects the presence or absence of skew in the addition signal and executes switching, and the first switch detects the presence or absence of skew in the addition signal A magnetic recording and reproducing device configured to perform switching. 2. Logic processing for instructing switching of the first switch -1- The impaction eye is created by logically processing a skew correction signal, a head switching pulse, and a fine slow start signal during slow playback. A magnetic recording/reproducing device according to claim 1.