JPS6328392B2 - - Google Patents
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- Publication number
- JPS6328392B2 JPS6328392B2 JP55105404A JP10540480A JPS6328392B2 JP S6328392 B2 JPS6328392 B2 JP S6328392B2 JP 55105404 A JP55105404 A JP 55105404A JP 10540480 A JP10540480 A JP 10540480A JP S6328392 B2 JPS6328392 B2 JP S6328392B2
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- JP
- Japan
- Prior art keywords
- signal
- frequency
- speed
- reproduced
- during
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000006243 chemical reaction Methods 0.000 claims description 5
- 238000001514 detection method Methods 0.000 description 8
- 238000010586 diagram Methods 0.000 description 5
- 230000010355 oscillation Effects 0.000 description 5
- 230000014759 maintenance of location Effects 0.000 description 4
- 239000003990 capacitor Substances 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- 230000005669 field effect Effects 0.000 description 2
- 238000013016 damping Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 231100000989 no adverse effect Toxicity 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
Description
【発明の詳細な説明】
本発明は磁気再生装置における変速再生装置に
係り、記録時と異なる磁気テープ走行速度で再生
を行なう変速再生時に、水平走査期間での時間軸
変動誤差を補正するよう、回転ヘツドの回転速度
及び／又は回転位相を制御することにより、画面
が流れる等の画面の品質劣化を生ぜしめることな
く高品質の変速再生を低コストの構成で行ない得
る変速再生装置を提供することを目的とする。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable speed playback device in a magnetic playback device, and includes a method for correcting time axis fluctuation errors in a horizontal scanning period during variable speed playback in which playback is performed at a magnetic tape running speed different from that during recording. To provide a variable speed playback device capable of performing high quality variable speed playback with a low cost configuration without causing deterioration of screen quality such as screen drift by controlling the rotational speed and/or rotational phase of a rotating head. With the goal.
一般のヘリカルスキヤン型磁気記録再生装置
（VTR）では、記録のテープ・ヘツド間相対線速
度と同一の相対線速度で磁気テープ上の記録トラ
ツクを再生する標準モード再生以外に、記録時と
異なるテープ・ヘツド間相対線速度で磁気テープ
上の記録トラツクを再生する変速再生が行なわれ
る。この変速再生は、通常回転ドラムの回転速度
は記録時のそれと常に一致させておき、磁気テー
プの走行速度を記録時のそれと異ならしめること
によつて、ステイル再生、スローモーシヨン再
生、フアーストモーシヨン再生、高速再生などを
行なうものである。例えば、ステイル再生のとき
は磁気テープの走行を停止させ、スローモーシヨ
ン再生のときは磁気テープの走行速度を記録時の
それよりも遅くし、フアーストモーシヨン再生及
び高速再生のときには磁気テープの走行速度を記
録時のそれよりも速くすることは周知の通りであ
る。 In a general helical scan type magnetic recording/reproducing device (VTR), in addition to the standard playback mode in which recorded tracks on a magnetic tape are played back at the same relative linear velocity as the relative linear velocity between the recording tape and the head, - Variable speed reproduction is performed in which recorded tracks on the magnetic tape are reproduced at the relative linear velocity between the heads. This variable speed playback is achieved by keeping the rotational speed of the rotating drum always the same as that during recording, and by making the running speed of the magnetic tape different from that during recording. It performs playback, high-speed playback, etc. For example, during still playback, the running of the magnetic tape is stopped, during slow-motion playback, the running speed of the magnetic tape is made slower than that during recording, and during fast-motion playback and high-speed playback, the running speed of the magnetic tape is It is well known that the speed is made faster than that during recording.
ここで、上記のVTRにより再生される記録ト
ラツクは、第１図にt1〜t5で示す如く、矢印Ｇ方
向に走行せしめられた磁気テープ１上に、回転ヘ
ツド（図示せず）により磁気テープ１の長手方向
に対して傾斜して形成されたものであり、１本の
トラツクには例えば１フイールド分の映像信号が
記録されており、かつ、相隣るトラツクは互いに
アジマス角の異なる回転ヘツドにより記録形成さ
れたものである。しかして、このような記録トラ
ツクを記録時と同一のテープ走行速度で再生する
標準モード再生では、当然のことながら回転ヘツ
ドの走査軌跡は記録トラツクの長手方向と平行の
軌跡となり、第１図示のトラツクt1を再生すると
きにはａで示す如き走査軌跡を描く。これに対
し、変速再生時にはテープ・ヘツド間の相対線速
度が記録時と異なることから、回転ヘツドの走査
軌跡は記録トラツクの長手方向とは平行にはなら
ず、例えばテープ走行速度を記録時の２倍として
トラツクt1を２倍速再生する場合は第１図にｂで
示す如く、トラツクt1よりt2に跨つて走査する軌
跡を描く。従つて、例えば第１図に示す如く、或
るトラツクの始端が次に形成された隣接トラツク
の始端から1.5H（Ｈは水平走査期間、以下同じ）
ずれており、水平同期信号が各トラツク間におい
て一定方向に並び揃えられて記録される（所謂Ｈ
並び記録）ようなトラツクパターンでの上記２倍
速再生時には、標準モード再生時に比し回転ヘツ
ドの再生水平走査期間は1.5H分減少したものと
なる。この結果、２倍速再生時には略0.6％の水
平走査周波数の誤差を生ずることになる。 Here, the recorded track to be reproduced by the VTR is placed on a magnetic tape 1 running in the direction of arrow G, as shown at t1 to t5 in FIG. 1, by a rotating head (not shown). It is formed to be inclined with respect to the longitudinal direction of the tape 1, and one track records, for example, a video signal for one field, and adjacent tracks are rotated at different azimuth angles. The record is formed by the head. However, in standard mode playback in which such a recording track is played back at the same tape running speed as during recording, the scanning locus of the rotary head is naturally parallel to the longitudinal direction of the recording track, which is the same as shown in Figure 1. When reproducing track t1 , a scanning locus as shown by a is drawn. On the other hand, during variable speed playback, the relative linear velocity between the tape and the head is different from that during recording, so the scanning locus of the rotating head is not parallel to the longitudinal direction of the recording track. When playing back track t1 at double speed, a scanning locus spanning from track t1 to track t2 is drawn, as shown by b in FIG. Therefore, for example, as shown in FIG. 1, the start end of a certain track is 1.5H from the start end of the next adjacent track formed (H is the horizontal scanning period, the same applies hereinafter).
The horizontal synchronization signals are recorded aligned in a certain direction between each track (so-called H
During double-speed playback using a track pattern such as (listed recording), the playback horizontal scanning period of the rotary head is reduced by 1.5H compared to the standard mode playback. As a result, an error in the horizontal scanning frequency of approximately 0.6% occurs during double speed reproduction.
この水平走査周波数の誤差は僅かであり、同様
にステイル再生時、スローモーシヨン再生時、記
録時の数倍までのテープ走行速度でのクイツクモ
ーシヨン再生時等においても水平走査周波数の誤
差が生ずるが、これらはいずれもVTRの再生出
力をモニターする一般市販のテレビジヨン受像機
の数％程度という水平同期保持範囲に含まれるわ
ずかな誤差にすぎず、モニター用テレビジヨン受
像機の再生画面には何の影響も与えない。 This error in the horizontal scanning frequency is small, and similarly, errors in the horizontal scanning frequency occur during still playback, slow motion playback, quick motion playback at tape running speeds up to several times the recording speed, etc. However, these are only slight errors within the horizontal synchronization retention range of a few percent of commercially available television receivers that monitor the playback output of VTRs; It has no effect.
しかるに、テープ走行速度を記録時の10倍乃至
20倍程度として磁気テープを記録時と同方向又は
逆方向に高速で走行せしめて再生を行なう高速再
生時には、上記の水平走査周波数の誤差はモニタ
ー用テレビジヨン受像機の水平同期保持範囲を逸
脱する程度に大となり問題が生ずる。このことに
つき第２図と共に更に説明するに、第２図は第１
図に示すトラツクパターンを更に簡略した模式的
パターンを示し、実線t1，t3，t5，…は同一のア
ジマス角の回転ヘツドCH1により記録形成され
たトラツクを示し、破線t2，t4，t6，…は回転ヘ
ツドCH1とは異なるアジマス角の同一の回転ヘ
ツドCH2により記録形成されたトラツクを示し、
ｔの添字はトラツクの記録形成時の順番を示す。 However, if the tape running speed is increased to 10 times the recording speed,
During high-speed playback, in which the magnetic tape is run at high speed in the same or opposite direction to the recording time at a magnification of about 20 times, the error in the horizontal scanning frequency mentioned above exceeds the horizontal synchronization retention range of the monitor television receiver. If the problem becomes large enough, a problem will occur. This will be further explained in conjunction with Figure 2. Figure 2 is similar to Figure 1.
A schematic pattern that is a further simplified version of the track pattern shown in the figure is shown, where solid lines t 1 , t 3 , t 5 , ... indicate tracks recorded and formed by the rotating head CH1 with the same azimuth angle, and broken lines t 2 , t 4 , t 6 , ... indicate the tracks recorded by the same rotary head CH2 with a different azimuth angle from the rotary head CH1,
The suffix t indicates the order in which the track records are formed.
第２図において、磁気テープ１を記録時の３倍
の速度で走行せしめて記録時と同一の回転速度の
回転ヘツドで再生を行なう３倍速フアーストモー
シヨン再生時には、磁気テープ１を記録時と同方
向Ｇに走行させたときの回転ヘツドの走査軌跡及
び走査方向は２点鎖線c1及びc2に示す如くにな
る。この場合の再生水平走査周波数の誤差はモニ
ター用テレビジヨン受像機の水平同期保持範囲内
に入る程度のものであり、再生画面への悪影響は
ない。 In FIG. 2, during triple-speed fast motion playback, in which the magnetic tape 1 is run at three times the speed during recording and the playback is performed using a rotary head that rotates at the same rotational speed as during recording, the magnetic tape 1 is moved at three times the speed during recording. The scanning locus and scanning direction of the rotary head when traveling in the same direction G are as shown by two-dot chain lines c1 and c2 . In this case, the error in the reproduction horizontal scanning frequency is within the horizontal synchronization retention range of the monitor television receiver, and has no adverse effect on the reproduction screen.
これに対し、磁気テープ１を記録時の例えば10
倍の速度で走行せしめて記録時と同一の回転速度
の回転ヘツドで再生を行なう高速再生時には、磁
気テープ１を記録時と同方向Ｇに走行させたとき
の回転ヘツドの走査軌跡及び走査方向は第２図に
１点鎖線の矢印d1，d2で示す如くになり、回転ヘ
ツドが所定期間再生したにもかかわらず再生水平
走査期間は、上記３倍速フアーストモーシヨン再
生時よりもはるかに減少する。なお、第２図は模
式化したものであり、実際は回転ヘツドの走査方
向は全てテープの走行方向Ｇに対して傾斜する。
しかし、回転ヘツドの走査位置は実際のトラツク
位置と同一である。 On the other hand, when recording magnetic tape 1, for example 10
During high-speed playback, in which the magnetic tape 1 is run at twice the speed and played back at the same rotational speed as during recording, the scanning locus and scanning direction of the rotating head when the magnetic tape 1 is run in the same direction G as during recording are As shown by the dashed-dotted arrows d 1 and d 2 in Fig. 2, even though the rotary head has regenerated for a predetermined period, the reproducing horizontal scanning period is much longer than during the above-mentioned triple-speed first motion reproducing. Decrease. Note that FIG. 2 is a schematic representation, and in reality, all the scanning directions of the rotary head are inclined with respect to the running direction G of the tape.
However, the scanning position of the rotating head is the same as the actual track position.
しかして、上記高速再生時には、標準モード再
生時の略６％程度の水平周波数の誤差（時間軸変
動）を生じ、これは上記したモニター用テレビジ
ヨン受像機の数％程度の水平同期保持範囲を逸脱
し、このため画面が流れてしまう等の弊害が生ず
ることがあつた。 However, during the above-mentioned high-speed playback, a horizontal frequency error (time axis fluctuation) of about 6% compared to standard mode playback occurs, which exceeds the horizontal synchronization holding range of about a few% of the above-mentioned monitor television receiver. This sometimes caused problems such as the screen being blurred.
本発明は上記欠点を除去したものであり、以下
第３図及び第４図と共にその一実施例について説
明する。 The present invention eliminates the above drawbacks, and an embodiment thereof will be described below with reference to FIGS. 3 and 4.
第３図は本発明装置の一実施例のブロツク系統
図、第４図は第３図の要部の一実施例の回路系統
図を示す。第３図において、２は回転ドラムで、
その周辺部近傍に180゜対向して互いにアジマス角
の異なる一対の回転ヘツド３ａ，３ｂが配設され
ており、ドラムモータ４と一体的に回転するよう
構成されている。ドラムモータ４は回転軸の一端
に円盤５が取付けられており、円盤５の周側面に
は180゜対向して一対の検出用マグネツト６ａ，６
ｂが配設されており、これらはドラムモータ４と
一体的に回転せしめられる。このドラムモータ４
の回転速度は、検出用マグネツト６ａ，６ｂが検
出ヘツド７のギヤツプ面とわずかに対向離間する
位置を通過する毎に取り出される検出ヘツド７の
出力パルスの繰り返し周波数によつて検出され
る。ただし、この検出ヘツド７の出力パルスは変
速再生時には用いられず、標準モード再生時に用
いられる。 FIG. 3 is a block diagram of an embodiment of the apparatus of the present invention, and FIG. 4 is a circuit diagram of an embodiment of the main part of FIG. In Figure 3, 2 is a rotating drum;
A pair of rotating heads 3a and 3b having different azimuth angles are disposed near the periphery of the drum motor 4, facing each other by 180 degrees, and are configured to rotate integrally with the drum motor 4. The drum motor 4 has a disk 5 attached to one end of its rotating shaft, and a pair of detection magnets 6a, 6 are mounted on the circumferential side of the disk 5, facing each other at 180 degrees.
b, which are rotated integrally with the drum motor 4. This drum motor 4
The rotational speed of the detection head 7 is detected by the repetition frequency of the output pulse of the detection head 7, which is taken out every time the detection magnets 6a, 6b pass a position slightly opposite to and spaced apart from the gap surface of the detection head 7. However, the output pulses of the detection head 7 are not used during variable speed reproduction, but are used during standard mode reproduction.
変速再生時の動作につき説明するに、この変速
再生時には切換スイツチ１１，２４は夫々固定端
子１１ｃ，２４ｃに接続される。また一方、回転
ドラム２の周側面に略180゜に亘つて添接された前
記第１図又は第２図に示す磁気テープ１が記録時
と異なる速度で走行せしめられる。磁気テープ１
の既記録FM映像信号は回転ヘツド３ａ，３ｂに
より再生され、その再生信号はピーキング回路及
びダンピング回路等を含む前置増幅器１４で所定
の信号処理が施された後、高域フイルタ１５、低
域フイルタ１８、及び水平同期信号分離回路２１
に夫々供給される。ここで、上記既記録FM映像
信号は、一例として色副搬送波周波数で1H毎に
90゜ずつ移相されている629kHzの低域変換搬送色
信号と、この信号より高域側の帯域を占めるFM
輝度信号との周波数分割多重信号であり、高域フ
イルタ１５によりFM輝度信号が周波数選択され
て取り出され、低域フイルタ１８により低域変換
搬送色信号が周波数選択されて取り出される。 To explain the operation during variable speed reproduction, during variable speed reproduction, the changeover switches 11 and 24 are connected to the fixed terminals 11c and 24c, respectively. On the other hand, the magnetic tape 1 shown in FIG. 1 or 2 attached approximately 180 degrees to the circumferential surface of the rotating drum 2 is run at a speed different from that during recording. magnetic tape 1
The recorded FM video signal is reproduced by the rotating heads 3a and 3b, and the reproduced signal is subjected to predetermined signal processing in a preamplifier 14 including a peaking circuit, a damping circuit, etc., and then passed through a high-frequency filter 15 and a low-frequency filter. Filter 18 and horizontal synchronization signal separation circuit 21
are supplied respectively. Here, as an example, the recorded FM video signal is transmitted every 1H at the color subcarrier frequency.
629kHz low-frequency conversion carrier color signal phase-shifted by 90° and FM occupying the higher frequency band than this signal.
The FM luminance signal is frequency-selected and extracted by the high-pass filter 15, and the low-pass converted carrier color signal is frequency-selected and extracted by the low-pass filter 18.
上記高域フイルタ１５よりのFM輝度信号は
FM復調回路１６によりFM復調されて再生輝度
信号とされた後、リミツタ回路等を含む映像増幅
器１７を経て混合器２７に供給される。一方、上
記低域フイルタ１８よりの低域変換搬送色信号
は、ACC回路、APC回路、メインコンバータ等
を含む周波数変換器１９に供給され、ここで後述
する誤差信号処理回路２２内の自動周波数制御回
路（AFC回路）２３よりの信号により所定の周
波数変換が行なわれる。更に水平同期信号分離回
路２１により分離された水平同期信号はAFC回
路２３に供給される。 The FM brightness signal from the above high-pass filter 15 is
After being FM demodulated by the FM demodulation circuit 16 into a reproduced luminance signal, it is supplied to the mixer 27 via the video amplifier 17 including a limiter circuit and the like. On the other hand, the low-pass converted carrier color signal from the low-pass filter 18 is supplied to a frequency converter 19 including an ACC circuit, an APC circuit, a main converter, etc., and is used for automatic frequency control within an error signal processing circuit 22, which will be described later. A predetermined frequency conversion is performed by a signal from the circuit (AFC circuit) 23. Furthermore, the horizontal synchronization signal separated by the horizontal synchronization signal separation circuit 21 is supplied to the AFC circuit 23.
ここで、AFC回路２３は切換スイツチ２４、
増幅器２５及びリミツタ２６と共に第４図に示す
如き回路の誤差信号処理回路２２の一部を構成し
ている。上記水平同期信号は第４図に示す単安定
マルチバイブレータ２９に印加され、ここでデユ
ーテイサイクル75％の矩形波に変換された後、基
準信号として位相比較器３６に供給され、1/10分
周器３５よりの水平走査周波数Hの信号と位相比
較され、それらの位相誤差に応じた位相誤差電圧
とされる。この位相誤差電圧は電圧制御発振器
（VCO）３７に制御電圧として印加され、その出
力発振周波数を制御する。VCO３７は160Hの周
波数又はその近傍周波数を発振出力し、４ビツト
カウンタ３０内の1/16分周器３４に印加する。従
つてこの1/16分周器３４は10H付近の周波数を出
力して1/10分周器３５に印加する。 Here, the AFC circuit 23 includes a changeover switch 24,
Together with the amplifier 25 and the limiter 26, it constitutes a part of the error signal processing circuit 22 of the circuit shown in FIG. The horizontal synchronizing signal is applied to the monostable multivibrator 29 shown in FIG. 4, where it is converted into a rectangular wave with a duty cycle of 75%, and then supplied as a reference signal to the phase comparator 36, which is 1/10 The phase is compared with the signal of the horizontal scanning frequency H from the frequency divider 35, and a phase error voltage is generated according to the phase error. This phase error voltage is applied as a control voltage to the voltage controlled oscillator (VCO) 37 to control its output oscillation frequency. The VCO 37 outputs oscillation at a frequency of 160 H or a frequency close thereto, and applies it to the 1/16 frequency divider 34 in the 4-bit counter 30. Therefore, the 1/16 frequency divider 34 outputs a frequency around 10 H and applies it to the 1/10 frequency divider 35.
このような比較動作によつて、水平同期信号２
１により分離出力された水平同期信号の周波数H
に100％追従した正確な160Hの信号がVCO３７
より発振出力され、この160Hの発振出力は1/2分
周器３２により80Hとされてデータセレクタ３８
の入力端子Ａに印加される一方、1/4分周器３３
により40Hとされてデータセレクタ３８の入力端
子Ｂに印加される。一方、単安定マルチバイブレ
ータ２９により得られた水平走査周波数Hの矩形
波は４ビツトカウンタ３０内の1/2分周器３１に
よりH／２とされてデータセレクタ３８の入力端
子Ｃに印加されると同時に、フリツプフロツプ４
１に印加される。以上がカラーAFC回路２３の
主要部の動作である。 Through such a comparison operation, the horizontal synchronization signal 2
Frequency H of the horizontal synchronization signal separated and output by 1
An accurate 160H signal that follows 100% of the VCO37
This oscillation output of 160 H is converted to 80 H by the 1/2 frequency divider 32 and sent to the data selector 38.
while the 1/4 frequency divider 33
The signal is set to 40 H and applied to the input terminal B of the data selector 38. On the other hand, the rectangular wave of horizontal scanning frequency H obtained by the monostable multivibrator 29 is converted to H /2 by the 1/2 frequency divider 31 in the 4-bit counter 30 and applied to the input terminal C of the data selector 38. At the same time, flip-flop 4
1. The above is the operation of the main parts of the color AFC circuit 23.
上記データセレクタ３８はその出力端子Ｑ又は
Ｑより抵抗R14又はR15を介して周波数変換器４
２に、周波数が前記低域変換搬送色信号の色副搬
送波周波数629kHz（＝40H）に等しく、かつ、位
相が1H毎に90゜ずつ順次推移する信号を供給し、
ここで入力端子４６よりの発振器（図示せず）の
出力3.58MHzと周波数変換させる。これにより、
周波数変換器４２より帯域フイルタ４３を通して
周波数が4.2MHzで位相が1H毎に90゜ずつ順次推移
せしめられた信号が取り出され、この信号は前記
周波数変換器１９に印加される。この周波数変換
器１９には帯域629kHz±500kHzで、かつ、位相
が1H毎に90゜ずつ順次推移せしめられている低域
変換搬送色信号が供給されているため、上記帯域
フイルタ４３の出力信号との周波数変換によつ
て、帯域3.58MHz±500kHzで位相推移のないもと
の搬送色信号が取り出される。この周波数変換器
１９より取り出された再生搬送色信号は、第１図
に示す映像増幅器２０を経て混合器２７に供給さ
れ、ここで映像増幅器１７よりの再生輝度信号と
多重されて再生カラー映像信号とされた後出力端
子２８より出力され、更に所定の信号処理系を経
てモニター用テレビジヨン受像機にて再生表示さ
れる。 The data selector 38 is connected to the frequency converter 4 via a resistor R14 or R15 from its output terminal Q or Q.
2, supplying a signal whose frequency is equal to the color subcarrier frequency of 629kHz (= 40H ) of the low-pass conversion carrier color signal and whose phase sequentially changes by 90° every 1H;
Here, the frequency is converted to the output 3.58MHz of an oscillator (not shown) from the input terminal 46. This results in
A signal having a frequency of 4.2 MHz and a phase shifted by 90 degrees every 1H is taken out from the frequency converter 42 through a band filter 43, and this signal is applied to the frequency converter 19. Since this frequency converter 19 is supplied with a low-pass converted carrier color signal having a band of 629kHz±500kHz and whose phase is sequentially shifted by 90 degrees every 1H, the output signal of the band filter 43 and By frequency conversion, the original carrier color signal with no phase shift is extracted in a band of 3.58MHz±500kHz. The reproduced carrier color signal taken out from the frequency converter 19 is supplied to the mixer 27 via the video amplifier 20 shown in FIG. 1, where it is multiplexed with the reproduced luminance signal from the video amplifier 17 to produce a reproduced color video signal. After that, the signal is outputted from the output terminal 28, and further passed through a predetermined signal processing system and reproduced and displayed on a monitor television receiver.
なお、データセレクタ３８の端子F2〜F7には
端子３９，４０及び４４より夫々出力端子Ｑ，
の状態を決定する信号が供給される。また端子４
５にはIDパルスが供給されるとともに、フリツ
プフロツプ４１のＱ，出力でデータセレクタ３
８のＱ，出力をダイオードD1，D2を介して制
御し、データセレクタ３８のＱ，のどちらか一
方をデータセレクタ３８の実際の出力とするが、
これらの回路自体は特に本発明の要旨とは関係が
ないのでその詳細な説明は省略する。 Note that the terminals F 2 to F 7 of the data selector 38 are connected to the output terminals Q and 44 from the terminals 39, 40, and 44, respectively.
A signal is provided that determines the state of the . Also terminal 4
5 is supplied with an ID pulse, and the data selector 3 is supplied with the Q output of flip-flop 41.
The Q output of the data selector 38 is controlled through the diodes D 1 and D 2 , and one of the Q outputs of the data selector 38 is set as the actual output of the data selector 38.
Since these circuits themselves are not particularly relevant to the gist of the present invention, detailed explanations thereof will be omitted.
次に本発明の要部につき説明するに、第４図に
示す位相比較器３６より取り出されたカラー
AFC回路２３に用いられる位相誤差電圧は、前
記した切換スイツチ２４を介して増幅器２５を構
成する電界効果トランジスタＸのゲートに印加さ
れる。この電界効果トランジスタＸはソースフオ
ロワを構成しており、そのソースと接地間に抵抗
R1が接続されており、ゲート入力位相誤差電圧
をインピーダンス変換して抵抗R5を介して演算
増幅器４７の反転入力端子に印加する。この演算
増幅器４７の出力端子と反転入力端子との間に
は、コンデンサC2及び抵抗R6の直列回路と、抵
抗R7及び可変抵抗器R8の直列回路とコンデンサ
C1とが夫々並列に接続されており、また演算増
幅器４７の非反転入力端子は、電源端子と接地間
に直列に接続されている抵抗R2、可変抵抗器R3
及び抵抗R4のうち可変抵抗器R3の摺動子に接続
されている。抵抗R2，R3及びR4はドラムモータ
４の回転速度のセンター調整として、抵抗R5，
R6、コンデンサC1，C2は周波数特性補正として、
また抵抗R7，R8、及び後述する抵抗R9，R10はゲ
イン調整として夫々機能する。 Next, to explain the main part of the present invention, the color taken out from the phase comparator 36 shown in FIG.
The phase error voltage used in the AFC circuit 23 is applied to the gate of the field effect transistor X constituting the amplifier 25 via the changeover switch 24 described above. This field effect transistor X constitutes a source follower, and there is a resistance between its source and ground.
R1 is connected, and the gate input phase error voltage is impedance-converted and applied to the inverting input terminal of the operational amplifier 47 via the resistor R5 . Between the output terminal and the inverting input terminal of this operational amplifier 47, a series circuit of a capacitor C 2 and a resistor R 6 , a series circuit of a resistor R 7 and a variable resistor R 8 , and a capacitor are connected.
C 1 are connected in parallel, and the non-inverting input terminal of the operational amplifier 47 is connected to a resistor R 2 and a variable resistor R 3 that are connected in series between the power supply terminal and ground.
and is connected to the slider of variable resistor R 3 of resistor R 4 . Resistors R 2 , R 3 and R 4 serve as center adjustment for the rotational speed of the drum motor 4, and resistors R 5 ,
R 6 and capacitors C 1 and C 2 are for frequency characteristic correction.
Further, resistors R 7 and R 8 and resistors R 9 and R 10 (described later) each function as a gain adjustment.
演算増幅器４７で増幅された位相誤差電圧は抵
抗R9及びR10の接続点より取り出され、切換スイ
ツチ１１を通して第３図示のデイスクリ制御系１
２に印加される。ここで、抵抗R10の一端には抵
抗R9が接続されているが、抵抗R10の他端には、
第４図に示す如くダイオードD3及びD4の直列回
路とダイオードD5及びD6の直列回路とが夫々並
列接続された回路を介して可変抵抗器R12の摺動
子に接続されている。この可変抵抗器R12は抵抗
R11，R13と共に電源端子と接地間に直列に接続
されており、ロツク範囲の中心値を設定するため
に用いられる。またダイオードD3〜D6はロツク
範囲を決定するもので、抵抗R11〜R13と共にリ
ミツタ２６を構成している。このリミツタ２６は
増幅器２５の出力位相誤差電圧が過大となつた時
には上限を制限し、過小となつた時にはリミツタ
２６より直流電圧を位相誤差電圧に付加するよう
動作する。また増幅器２５側の調整によりドラム
モータ４の安定した制御が行なわれる。 The phase error voltage amplified by the operational amplifier 47 is taken out from the connection point between the resistors R9 and R10 , and is passed through the changeover switch 11 to the disk control system 1 shown in the third figure.
2. Here, resistor R9 is connected to one end of resistor R10 , and the other end of resistor R10 is connected to
As shown in FIG. 4, a series circuit of diodes D 3 and D 4 and a series circuit of diodes D 5 and D 6 are connected to the slider of a variable resistor R 12 through parallel-connected circuits. . This variable resistor R 12 is a resistance
It is connected in series with R 11 and R 13 between the power supply terminal and ground, and is used to set the center value of the lock range. The diodes D 3 to D 6 determine the lock range, and together with the resistors R 11 to R 13 constitute a limiter 26. This limiter 26 operates to limit the upper limit when the output phase error voltage of the amplifier 25 becomes too large, and to add a DC voltage to the phase error voltage when it becomes too small. Furthermore, the drum motor 4 can be stably controlled by adjusting the amplifier 25 side.
このようにして、切換スイツチ１１より取り出
された再生水平同期信号の基準位相に対する位相
誤差に応じた電圧は、第３図に示すデイスクリ制
御系１２、モータ駆動増幅器１３を夫々経てドラ
ムモータ４に印加される。またこのドラムモータ
４の回転に応じた繰り返し周波数のFGパルスが
検出され（その検出機構は図示せず）、デイスク
リ制御系１２に印加されてドラムモータ４の回転
速度を制御する閉ループが構成される。これによ
り、ドラムモータ４はリミツタ２６よりの位相誤
差電圧によつて回転速度及び／又は回転位相が再
生水平走査周波数の誤差を補正する方向に制御さ
れる。 In this way, the voltage corresponding to the phase error with respect to the reference phase of the reproduced horizontal synchronizing signal taken out from the changeover switch 11 is applied to the drum motor 4 through the disc control system 12 and the motor drive amplifier 13 shown in FIG. be done. Further, an FG pulse with a repetition frequency corresponding to the rotation of the drum motor 4 is detected (the detection mechanism is not shown), and is applied to the disc control system 12 to form a closed loop that controls the rotation speed of the drum motor 4. . Thereby, the rotational speed and/or rotational phase of the drum motor 4 is controlled by the phase error voltage from the limiter 26 in a direction that corrects the error in the reproduced horizontal scanning frequency.
ここで、いま回転ヘツドが第２図にd1，d2で示
す如き走査軌跡を描く高速再生時には、再生水平
同期信号の周波数は標準モード再生時の略６％低
下する。この結果、第４図に示す位相比較器３６
からの位相誤差電圧は増加し、これに伴つてドラ
ムモータ４の回転は減少せしめられる。従つて上
記再生水平同期信号の周波数は所定範囲内にまで
補正される。すなわち、磁気テープ１を記録時の
10倍の速度で走行せしめるような高速再生時に、
回転ヘツド３ａ，３ｂの再生水平同期信号数が減
少することによつて回転ヘツド３ａ，３ｂの1H
間の走査時間が長くなる現象に対して、回転ドラ
ム４の回転速度及び／又は回転位相を制御して回
転ヘツド３ａ，３ｂの走査速度を高め、これによ
り標準モード再生時における水平同期信号の周期
に一致せしめんとするものである。 Now, during high-speed reproduction in which the rotating head traces scanning trajectories as shown by d 1 and d 2 in FIG. 2, the frequency of the reproduction horizontal synchronizing signal decreases by about 6% compared to standard mode reproduction. As a result, the phase comparator 36 shown in FIG.
The phase error voltage increases, and the rotation of the drum motor 4 decreases accordingly. Therefore, the frequency of the reproduced horizontal synchronizing signal is corrected to within a predetermined range. That is, when recording the magnetic tape 1,
During high-speed playback, such as running at 10 times the speed,
1H of the rotary heads 3a, 3b by decreasing the number of reproducing horizontal synchronization signals of the rotary heads 3a, 3b.
In order to deal with the phenomenon that the scanning time becomes longer during normal mode playback, the scanning speed of the rotating heads 3a and 3b is increased by controlling the rotational speed and/or rotational phase of the rotating drum 4, thereby reducing the period of the horizontal synchronizing signal during standard mode playback. It is intended to be consistent with the following.
なお、回転ヘツド３ａ，３ｂの回転速度を高め
ることによつて１トラツクの走査時間が速めら
れ、この結果、垂直走査周波数も当然高められる
が、モニター用テレビジヨン受像機の垂直同期保
持範囲は垂直走査周波数の十数％の誤差の周波数
まであり、水平同期保持範囲よりも格段に広いた
め、上記の補正によつて水平走査周波数を高めて
も垂直の同期はとれる。例えば、トリガータイプ
の発振回路のテレビジヨン受像機の場合は、自走
発振周波数を約54Hz以下に調整することによつ
て、高速再生時に上記の補正をしても垂直の同期
はとれる。 Incidentally, by increasing the rotational speed of the rotary heads 3a and 3b, the scanning time for one track is shortened, and as a result, the vertical scanning frequency is naturally increased, but the vertical synchronization retention range of the monitor television receiver is There are frequencies with an error of more than ten percent of the scanning frequency, which is much wider than the horizontal synchronization holding range, so even if the horizontal scanning frequency is increased by the above correction, vertical synchronization can be achieved. For example, in the case of a television receiver with a trigger-type oscillation circuit, by adjusting the free-running oscillation frequency to approximately 54 Hz or less, vertical synchronization can be achieved even with the above correction during high-speed playback.
このように、本発明はテレビジヨン受像機の垂
直同期保持範囲が水平同期保持範囲よりも格段に
広いことに着目し、変速再生時に回転ドラムの回
転速度及び／又は回転位相を制御することによ
り、水平走査周波数を補正し、水平同期がはずれ
ることによつて生ずる画面が流れることなどを防
止したものである。 Thus, the present invention focuses on the fact that the vertical synchronization holding range of a television receiver is much wider than the horizontal synchronization holding range, and by controlling the rotational speed and/or rotational phase of the rotating drum during variable speed playback, This corrects the horizontal scanning frequency and prevents the screen from drifting due to loss of horizontal synchronization.
なお、上記実施例では磁気テープ１を記録時と
同方向に走行させて高速再生を行なつた場合につ
いて説明したが、記録時と逆方向に走行させて高
速再生を行なう場合にも同様に適用でき、更に他
の変速再生時にも同様に適用できることは明らか
である。 In the above embodiment, the case where high-speed playback is performed by running the magnetic tape 1 in the same direction as during recording has been described, but the present invention is similarly applicable to the case where high-speed playback is performed by running the magnetic tape 1 in the opposite direction to that during recording. It is clear that the present invention can be similarly applied to other variable speed playbacks.
なお、第３図示の装置において、標準モード再
生時には、切換スイツチ１１，２４は固定端子１
１ｂ，２４ｂ側に接続される。これにより、デイ
スクリ制御系１２に印加される位相誤差信号は、
検出ヘツド７の出力パルスを台形波形成回路８を
通して得た台形波の傾斜部を、位相比較器１０に
おいて、基準信号発生回路９よりの基準信号でサ
ンプリングホールドして得た。ドラムモータ４の
回転位相誤差に応じた位相誤差信号となり、周知
のドラムサーボ系が構成される。 In the device shown in the third figure, during standard mode playback, the changeover switches 11 and 24 are connected to the fixed terminal 1.
It is connected to the 1b and 24b sides. As a result, the phase error signal applied to the disc control system 12 is
The slope part of the trapezoidal wave obtained by passing the output pulse of the detection head 7 through the trapezoidal wave forming circuit 8 was sampled and held in the phase comparator 10 using a reference signal from the reference signal generating circuit 9. This becomes a phase error signal corresponding to the rotational phase error of the drum motor 4, and constitutes a well-known drum servo system.
上述の如く、本発明になる磁気再生装置におけ
る変速再生装置は、磁気テープを記録時とは異な
る速度で走行せしめて再生する変速再生時に、
AFC回路の一部より取り出された再生水平同期
信号の周波数に応じた誤差信号を振幅制限するリ
ミツタと、リミツタの出力信号に基づいて回転ヘ
ツドを回転するモータの回転速度及び回転位相の
少なくとも一方を制御する制御手段とを具備し、
変速再生時に前記再生水平同期信号の周波数誤差
を補正するよう構成したため、周波数誤差補正用
誤差信号を得るための専用回路が不要になり、低
コストで構成することができ、また例えば誤差信
号が過大になつた時には上限の制限され、過小と
なつた時には上記リミツタ側より直流電圧が付加
され、よつて常に回転ヘツドは所定の回転速度範
囲を保持し、外乱による誤差電圧の上昇等に対し
ても安定した制御を行なうことができる等の数々
の特長を有するものである。 As described above, the variable speed playback device in the magnetic playback device according to the present invention is capable of performing variable speed playback during playback by running the magnetic tape at a speed different from that during recording.
A limiter that limits the amplitude of an error signal according to the frequency of the reproduced horizontal synchronization signal extracted from a part of the AFC circuit, and at least one of the rotational speed and rotational phase of the motor that rotates the rotary head based on the output signal of the limiter. and a control means for controlling,
Since the structure is configured to correct the frequency error of the reproduced horizontal synchronizing signal during variable speed playback, a dedicated circuit for obtaining an error signal for frequency error correction is not required, and the structure can be configured at low cost. When it becomes too low, the upper limit is applied, and when it becomes too small, DC voltage is applied from the limiter side, so that the rotating head always maintains the specified rotational speed range, and even against increases in error voltage due to disturbances, etc. It has many features such as being able to perform stable control.
第１図は本発明装置で再生され得る磁気テープ
の記録トラツクパターンの一例を示す図、第２図
は変速再生時の回転ヘツドの走査軌跡及び走査方
向を記録トラツクパターンとともに示す図、第３
図は本発明装置の一実施例を示すブロツク系統
図、第４図は第３図の要部の一実施例を示す回路
系統図である。
１……磁気テープ、２……回転ドラム、３ａ，
３ｂ……回転ヘツド、４……ドラムモータ、１
１，２４……切換スイツチ、１２……デイスクリ
制御系、２１……水平同期信号分離回路、２２…
…誤差信号処理回路、２３……自動周波数制御回
路（AFC回路）、２６……リミツタ、２８……再
生カラー映像信号出力端子、３０……４ビツトカ
ウンタ、３６……位相比較器、３８……データセ
レクタ、４７……演算増幅器。
FIG. 1 is a diagram showing an example of a recording track pattern of a magnetic tape that can be reproduced by the apparatus of the present invention, FIG.
The figure is a block system diagram showing an embodiment of the apparatus of the present invention, and FIG. 4 is a circuit system diagram showing an embodiment of the main part of FIG. 1...magnetic tape, 2...rotating drum, 3a,
3b... Rotating head, 4... Drum motor, 1
1, 24...Switchover switch, 12...Discrete control system, 21...Horizontal synchronization signal separation circuit, 22...
... Error signal processing circuit, 23 ... Automatic frequency control circuit (AFC circuit), 26 ... Limiter, 28 ... Reproduction color video signal output terminal, 30 ... 4-bit counter, 36 ... Phase comparator, 38 ... Data selector, 47... operational amplifier.
Claims (1)
ツクの既記録信号を回転ヘツドにより再生し、そ
の再生信号中の低域変換搬送色信号を周波数変換
器にて正規の搬送色信号に戻すための周波数変換
用信号を再生水平同期信号に基づいて生成出力す
るAFC回路を備えた磁気再生装置において、前
記磁気テープを記録時とは異なる速度で走行せし
めて再生する変速再生時に、前記AFC回路の一
部より取り出された再生水平同期信号の周波数に
応じた誤差信号を振幅制限するリミツタと、該リ
ミツタの出力信号に基づいて前記回転ヘツドを回
転するモータの回転速度及び回転位相の少なくと
も一方を制御する制御手段とを具備し、該変速再
生時に該再生水平同期信号の周波数誤差を補正す
るよう構成したことを特徴とする磁気再生装置に
おける変速再生装置。1 Frequency for reproducing a previously recorded signal on a track tilted with respect to the longitudinal direction of the magnetic tape using a rotary head, and converting a low frequency converted carrier color signal in the reproduced signal back to a regular carrier color signal using a frequency converter. In a magnetic reproducing device equipped with an AFC circuit that generates and outputs a conversion signal based on a reproduction horizontal synchronization signal, a part of the AFC circuit is used during variable speed reproduction in which the magnetic tape is run at a speed different from that during recording and reproduced. a limiter that limits the amplitude of the error signal according to the frequency of the reproduced horizontal synchronization signal extracted from the output signal, and control that controls at least one of the rotational speed and rotational phase of the motor that rotates the rotary head based on the output signal of the limiter. A variable speed reproducing device in a magnetic reproducing device, comprising means for correcting a frequency error of the reproduced horizontal synchronizing signal during the variable speed reproduction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10540480A JPS5730473A (en) | 1980-07-31 | 1980-07-31 | Variable-speed reproducing device of magnetic reproducing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10540480A JPS5730473A (en) | 1980-07-31 | 1980-07-31 | Variable-speed reproducing device of magnetic reproducing device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5730473A JPS5730473A (en) | 1982-02-18 |
| JPS6328392B2 true JPS6328392B2 (en) | 1988-06-08 |
Family
ID=14406671
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10540480A Granted JPS5730473A (en) | 1980-07-31 | 1980-07-31 | Variable-speed reproducing device of magnetic reproducing device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5730473A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01172390U (en) * | 1988-05-26 | 1989-12-06 |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59168853U (en) * | 1983-04-25 | 1984-11-12 | 日本ビクター株式会社 | Head servo circuit |
| JPS59219082A (en) * | 1983-05-27 | 1984-12-10 | Hitachi Ltd | Magnetic video recording and reproducing device |
| US5066196A (en) * | 1988-04-21 | 1991-11-19 | Usui Kokusai Sangyo Kabushiki Kaisha | Engine-cooling fan made of synthetic resin |
-
1980
- 1980-07-31 JP JP10540480A patent/JPS5730473A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01172390U (en) * | 1988-05-26 | 1989-12-06 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5730473A (en) | 1982-02-18 |
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|---|---|---|
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