JPH01117592A - Nonstandard signal discrimination circuit - Google Patents
Nonstandard signal discrimination circuitInfo
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- JPH01117592A JPH01117592A JP62276135A JP27613587A JPH01117592A JP H01117592 A JPH01117592 A JP H01117592A JP 62276135 A JP62276135 A JP 62276135A JP 27613587 A JP27613587 A JP 27613587A JP H01117592 A JPH01117592 A JP H01117592A
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- signal
- phase
- discrimination
- standard
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- 238000001514 detection method Methods 0.000 claims abstract description 19
- 230000000630 rising effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000001960 triggered effect Effects 0.000 description 2
- 239000002131 composite material Substances 0.000 description 1
- 238000012850 discrimination method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 230000002123 temporal effect Effects 0.000 description 1
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- Processing Of Color Television Signals (AREA)
- Color Television Systems (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は任意に与えられたＮＴＳＣカラー映像信号の水
平同期信号と色副搬送波の位相関係が非同期であるか否
かを検出するＮＴＳＣ非標準信号判別回路に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is an NTSC non-standard signal discrimination method for detecting whether or not the phase relationship between the horizontal synchronization signal and the color subcarrier of an arbitrarily given NTSC color video signal is asynchronous. It is related to circuits.
従来の技術
一般にＮＴＳＣカラー映像信号と呼ばれるのは、まず標
準信号と非標準信号の２つに大別される。BACKGROUND OF THE INVENTION NTSC color video signals, which are generally called NTSC color video signals, are roughly divided into two types: standard signals and non-standard signals.
前者でいう標準信号とは水平同期信号、垂直同期信号及
び色副搬送波が時間的ジッターをもたず下記の０）式、
＠）式の関係を満たす信号をいう。In the former case, the standard signal is one in which the horizontal synchronization signal, vertical synchronization signal, and color subcarrier have no temporal jitter, and the following formula 0) is used.
@) refers to a signal that satisfies the relationship of formula.
９１０ Ｘ ｆＨ”” ４ Ｘ ｆＢｃ・・−−−−−
−−−−−（１）５２５ Ｘ ｆＨ＝２ Ｘ ｆｙ
・・・・・・・・・・・・Ｇ２）ｆｓｃ：色副搬
送波の周波数
ｆＨ：水平同期信号の周波数
ｆｖ ：垂直同期信号の周波数
例えば、カメラの出力、ＶＴＲの時間軸変動をなくすＴ
ＢＣの出力、コンポジット映像信号発生器の出力などが
前述の標準信号にあたる。910 X fH"" 4 X fBc...---
-----(1) 525 X fH=2 X fy
・・・・・・・・・・・・G2) fsc: Frequency of color subcarrier fH: Frequency of horizontal synchronization signal fv: Frequency of vertical synchronization signal For example, T to eliminate time axis fluctuation of camera output, VTR
The output of the BC, the output of the composite video signal generator, etc. correspond to the aforementioned standard signals.
次に後者でいう非標準信号とは水平同期信号。Next, the latter non-standard signal is the horizontal synchronization signal.
垂直同期信号及び色副搬送波が時間軸変動をもち、前記
（１）式の関係を満たさない信号をいう。例えば、ＶＨ
３方式、β方式のＶＴＲの再生出力や、ＸインチＶＴＲ
の再生出力などが前述の非標準信号にあたる。This refers to a signal in which the vertical synchronization signal and the color subcarrier have time axis fluctuations and do not satisfy the relationship in equation (1) above. For example, VH
3 system, β system VTR playback output, X inch VTR
The playback output etc. correspond to the aforementioned non-standard signals.
前述のような標準信号と非標準信号が混在するかで、映
像信号を扱うＶＴＲやビデオスイッチャ−などは同レベ
ルで入力として受けつけざるを得ない。したがって前記
の映像信号を扱う装置は手動で標準信号か非標準信号で
あるかの入力切換スイッチが設けられているが、市場の
要望として非標準信号であるかどうかの自動判別装置が
、映像信号を扱う装置に設けられることが望まれている
。Due to the mixture of standard and non-standard signals as described above, VTRs, video switchers, etc. that handle video signals have no choice but to accept them as input at the same level. Therefore, the above-mentioned devices that handle video signals are equipped with an input switch that manually selects whether the video signal is a standard signal or a non-standard signal. It is desired that the system be installed in equipment that handles.
以上の背景のなかでみられた従来の非標準信号判別回路
のブロック図を第６図に示す。FIG. 6 shows a block diagram of a conventional non-standard signal discrimination circuit that was developed against the above background.
第６図において１位相比較器２７．増幅器２９゜電圧制
御発振器３１９分局器３３を含めたループは、入力映像
信号２４の水平同期信号２６に同期させたｎ倍のｆＨ（
ｎは整数）３２を発生させるためのＰＬＬで、ＶＴＲで
はよく導入されているブロックである。以上のＰＩ、Ｌ
を利用して、電圧制御発振器３１を制御する電圧３ｏの
動きを２つの電圧比較器３５．３６を設けて非標準信号
であるかどうかを判別しようとするものである。前記２
つの電圧比較器３５．３６では電圧の上限値と下＠値を
それぞれ定めて＞、６、いずれかのしきい値を越えた時
に非標準信号と判別するようになっている。すなわち、
入力映像信号が標準信号の時は水平同期信号に時間軸変
動をもっていないので、Ｐ Ｌ Ｌ ／Ｌ／−プ内の電
圧制御発振器３１を制御する電圧３ｏは安定しておシ、
２つの電圧比較器３６゜３６のしきい値を越えることは
ない。一方、入力映像信号が非標準信号のときは水平同
期信号に時間軸変動をもっているので、電圧比較器３５
．３６の入力３ｏは水平同期信号の位相変動に伴なって
電圧が振れるので、前記２つの電圧比較器３６゜３６の
いずれかのしきい値を越えることになυ非標準信号と判
別することができる。ＶＴＲの再生信号の場合ヘッド切
換時に大きなスキューが生じこの位相誤差を検出するこ
ととなる。In FIG. 6, one phase comparator 27. A loop including an amplifier 29, a voltage controlled oscillator 319, and a branching unit 33 has an fH (n times) synchronized with the horizontal synchronization signal 26 of the input video signal 24
This is a PLL for generating 32 (n is an integer), and is a block often installed in VTRs. The above PI, L
By using this, two voltage comparators 35 and 36 are provided to determine whether the movement of the voltage 3o that controls the voltage controlled oscillator 31 is a non-standard signal. Said 2
The two voltage comparators 35 and 36 each determine an upper voltage value and a lower voltage value, and determine that the signal is a non-standard signal when it exceeds any one of the thresholds >, 6, and 6. That is,
When the input video signal is a standard signal, the horizontal synchronization signal has no time axis fluctuation, so the voltage 3o that controls the voltage controlled oscillator 31 in the PLL/L/- loop remains stable.
The thresholds of the two voltage comparators 36.degree. 36 are never exceeded. On the other hand, when the input video signal is a non-standard signal, the horizontal synchronization signal has time axis fluctuations, so the voltage comparator 35
．． Since the voltage at the input 3o of 36 fluctuates in accordance with the phase fluctuation of the horizontal synchronizing signal, it is impossible to distinguish it as a non-standard signal υ without exceeding the threshold of either of the two voltage comparators 36 and 36. can. In the case of a reproduced signal from a VTR, a large skew occurs when switching heads, and this phase error must be detected.
発明が解決しようとする問題点
前述の従来例によると水平同期信号の時間軸変動を電圧
に変換して電圧変動から検出しているため、しきい値の
設定が微妙になる。またＶＴＲの自己録再生信号の時間
軸変動はきわめて小さい場合もあシ、非標準信号の誤判
別を招くことがある。Problems to be Solved by the Invention According to the conventional example described above, the time axis fluctuation of the horizontal synchronization signal is converted into voltage and detected from the voltage fluctuation, so the setting of the threshold value becomes delicate. Furthermore, the time axis variation of the self-recording/reproducing signal of a VTR may be extremely small, which may lead to misidentification of a non-standard signal.
本発明はこのような従来の問題点を解消するものであり
、水平同期信号と色副搬送波の位相関係を検出すること
により確実な非標準信号の判別を可能とする非標準信号
判別回路提供するものである。The present invention solves these conventional problems and provides a non-standard signal discriminating circuit that enables reliable discrimination of non-standard signals by detecting the phase relationship between a horizontal synchronizing signal and a color subcarrier. It is something.
問題点を解決するための手段
本発明の非標準信号判別回路は、時間的に互に隣シ合っ
た水平期間の水平同期信号と色副搬送波の位相関係が一
定であるか否かを検出する第１の回路と、互いに隣り合
った水平期間の水平同期信号と色副搬送波の位相関係を
第１の回路の位相検出位置と違った位置で検出する第２
の回路をもち、第１の回路と第２の回路とが共に色副搬
送波の位相関係がずれていると検出した時に非標準信号
と判別するものである。Means for Solving the Problems The non-standard signal discriminating circuit of the present invention detects whether the phase relationship between the horizontal synchronizing signal and the color subcarrier in temporally adjacent horizontal periods is constant. a first circuit; and a second circuit that detects the phase relationship between the horizontal synchronizing signal and the color subcarrier in adjacent horizontal periods at a position different from the phase detection position of the first circuit.
When both the first circuit and the second circuit detect that the phase relationship of the color subcarriers is shifted, the signal is determined to be a non-standard signal.
作 用
水平期間ごとの水平同期信号との位相関係がずれている
かどうかが第１．第２の回路で検出される。単に位相関
係のずれを判別するには、前記第１の回路だけでよいの
であるが、水平同期信号を基準に色副搬送波の位相検出
をディジタル回路で構成した場合、５ＣＨ（水平同期信
号と色副搬送波の位相）がずれた標準信号において誤検
出するおそれがあるため、第２の回路を設は誤検出を防
止でいる。The first thing to check is whether the phase relationship with the horizontal synchronization signal for each horizontal period of action is shifted. Detected by a second circuit. To simply determine a shift in the phase relationship, it is sufficient to use only the first circuit, but if the phase detection of the color subcarrier is configured with a digital circuit based on the horizontal synchronization signal, then the 5CH (horizontal synchronization signal and color Since there is a risk of erroneous detection in a standard signal whose subcarrier phase is shifted, the second circuit is provided to prevent erroneous detection.
実施例
以下、本発明の一実施例の非標準信号判別回路を図面を
参照して説明する。Embodiment Hereinafter, a non-standard signal discrimination circuit according to an embodiment of the present invention will be explained with reference to the drawings.
第１図に示すように、水平同期信号と色副搬送波１の位
相差を検出する第１の検出回路を構成するＤフリップフ
ロップ２，４と、それらの位相関係の変動を検出する第
１の判別回路を構成するＥＸＣＬＵＳＩＶＥ−ＯＲｅと
時定数の長いリドリガーモノマルチ８とで第１の回路が
構成される。As shown in FIG. 1, D flip-flops 2 and 4 constitute a first detection circuit that detects a phase difference between a horizontal synchronizing signal and a color subcarrier 1, and a first D flip-flop that detects fluctuations in their phase relationship. A first circuit is constituted by EXCLUSIVE-ORe, which constitutes a discrimination circuit, and a ridrigger monomulti 8 having a long time constant.
そして下段の第２の検出回路を構成するＤフリップフロ
ップ１４．１６と第２の判別回路を構成するＥＸＣＩ、
ＵＳ Ｉ ＶＥ−ＯＲ１８とリドリガーモノマルチ２０
とで第２の回路が溝成されている。D flip-flops 14 and 16 constituting the second detection circuit in the lower stage and EXCI constituting the second discrimination circuit,
US I VE-OR18 and Ridriger Mono Multi 20
A second circuit is formed by the groove.
前段のモノマルチ１１は、第１回路と第２回路における
色副搬送波の位相検出位置を決定するものであシ、水平
同期信号を入力としてモノマルチ１１のＱ出力とＱ出力
で第１回路、第２回路に検出基準のクロックを供給して
いる。前述のように標準信号入力時に第１回路の誤検出
を防ぐためにモノマルチ１１の時定数ｔｗは次の条件で
なければならない。The monomulti 11 at the front stage determines the phase detection position of the color subcarrier in the first circuit and the second circuit.The first circuit, A detection reference clock is supplied to the second circuit. As mentioned above, in order to prevent erroneous detection of the first circuit when a standard signal is input, the time constant tw of the monomulti 11 must meet the following conditions.
但し、ｎ≧００整数である。However, n≧00 integer.
２２は第１の回路と第２の回路の出力の論理和を得るＯ
Ｒゲートである。22 is O to obtain the logical sum of the outputs of the first circuit and the second circuit.
This is the R gate.
次に種々の入力条件を想定して、第２図、第３図、第４
図のタイミング図を参照して本実施例の非標準信号判別
回路について説明する。Next, assume various input conditions, and
The non-standard signal discrimination circuit of this embodiment will be explained with reference to the timing diagram shown in the figure.
第２図では標準信号が入力された時の例を示す。FIG. 2 shows an example when a standard signal is input.
（ｎ−１）ライン、ｎラインの色副搬送波の位相をサン
プルパルスの立上りエッヂと立下シエッヂで検出する。The phase of the color subcarrier of the (n-1) line and the n line is detected by the rising edge and falling edge of the sample pulse.
第２図の例では隣シ同士のラインの色副搬送波の位相は
立上りエッヂで検出した場合も、立下りエッヂで検出し
た場合にも互いに反転し一’ＩＪ、第１回路、第２回路
のＥＸＣＬＵＳＩＶＥ−ＯＲ６，１８の出力はともにＨ
ＩＧＨレベルを保つ。したがって、リドリガーモノマル
チ８，２０は共にトリガーされないため、ＯＲゲート２
２出力はＨＩＧＨレベルで標準信号と判別した出力をす
る。In the example shown in Fig. 2, the phases of the color subcarriers of adjacent lines are reversed both when detected at the rising edge and when detected at the falling edge. EXCLUSIVE-OR6 and 18 outputs are both H
Maintain IGH level. Therefore, both Ridrigger Monomultis 8 and 20 are not triggered, so OR gate 2
The second output is a HIGH level output that is determined to be a standard signal.
第３図も標準信号が入力された時の例であるが、サング
ルパルスの立上シエッヂがｎフィンの立上りエッヂ、（
ｎ−１）ラインの立下シエッヂと一致した場合を示す。Figure 3 is also an example when a standard signal is input, but the rising edge of the sample pulse is the rising edge of the n-fin, (
n-1) This shows the case where the falling edge of the line coincides with the falling edge.
この時、第１回路の位相検出を行うＤフリップフロップ
２，４にとって、セットアツプタイム（データ保持時間
）を満たすか満たさないかの位置の場合は、たとえサン
プルパルスと色副搬送波の位相関係が一定であっても検
出回路の誤動作によ５ＨＩＧＨレベルを示したり、ＬＯ
Ｗレベルを示したシする。したがってＥＸＣＬＵＳＶＥ
−ＯＲθの出力は変動し、その結果リドリガーモノマル
チ８に対しトリガーを与え非標準信号との判別をしてし
まう。ところが、第２の回路の位相検出では、前述の（
３）式の条件を満たしティるため、ＥＸＣＩ、ＵＳＩＶ
Ｅ−ＯＲ１８の出力は変動せずリドリガーモノマルチ２
ｏはトリガーされない。よって、ＯＲゲート２２出力は
ＨＩＧＨレベル出力を行い標準信号との判別出力をする
。At this time, for the D flip-flops 2 and 4 that perform phase detection in the first circuit, if the set-up time (data retention time) is satisfied or not, even if the phase relationship between the sample pulse and the color subcarrier is Even if it is constant, it may show 5HIGH level due to malfunction of the detection circuit or LO
It shows the W level. Therefore EXCLUSVE
The output of -ORθ fluctuates, and as a result, it gives a trigger to the ridrigger monomulti 8 and discriminates it from a non-standard signal. However, in the phase detection of the second circuit, the above-mentioned (
3) In order to satisfy the conditions of the formula, EXCI, USIV
The output of E-OR18 does not fluctuate and the Ridrigger Mono Multi 2
o is not triggered. Therefore, the output of the OR gate 22 outputs a HIGH level and outputs a discrimination signal from the standard signal.
したがって、入力信号が標準信号であるならば、水平同
期信号にもとづくサンプルパルスと色副搬送波の位相関
係がいかなる位置にあっても標準信号であるものとして
安定に判別する。Therefore, if the input signal is a standard signal, it is stably determined as a standard signal no matter where the phase relationship between the sample pulse based on the horizontal synchronizing signal and the color subcarrier is.
次に、第４図にて非標準信号が入力された時について説
明する。このとき、水平同期信号と色副搬送波の相関が
ずれ、位相関係がずれることなく一定に保持されていな
いことがサンプルパルスの立上シエッヂでも立下りエッ
ヂでも検出され、ＥＸＣＬＵＳＩＶＥ−ＯＲ６，、１ｓ
の出力はＬＯＷレベルに変化しリドリガーモノマルチ８
，２ｏが両方とも作動してＯＲゲート２２出力はＬＯＷ
レベルとなって非標準信号と判別される。Next, the case when a non-standard signal is input will be explained with reference to FIG. At this time, the correlation between the horizontal synchronization signal and the color subcarrier is shifted, and the fact that the phase relationship is not maintained constant without shifting is detected at both the rising edge and the falling edge of the sample pulse, and EXCLUSIVE-OR6,,1s
The output changes to LOW level and the Ridrigger Mono Multi 8
, 2o are both activated and the OR gate 22 output is LOW.
level and is determined to be a non-standard signal.
上記のように本実施例によれば、非標準信号。As described above, according to this embodiment, a non-standard signal.
標準信号の判別をＳＣＨにずれがあった場合にも読まる
ことなく判別することが可能となるものである。This makes it possible to determine the standard signal without being read even if there is a shift in the SCH.
なお、水平同期信号と色副搬送波の周波数がわずかしか
すれてない場合、回路素子の遅延時のばらつきによって
位相ずれ検出が確実に行われないため、リドリガーモノ
マルチ８，２０の時定数としては、例えば１フイ一ルド
期間程度に十分長くとっておく必要がある。また本実施
例においては演算回路としてＯＲゲートを用いた溝成と
したが、論理が負論理であるかあるいは正論理であるが
、さらに前段の第１．第２の判別回路の出力のとシ方に
よって適宜公知の回路を用いて購成されるものである。In addition, if the frequency of the horizontal synchronization signal and the color subcarrier are slightly different, phase shift detection cannot be performed reliably due to variations in the delay of the circuit elements, so the time constant of the Ridrigger Mono Multi 8 and 20 is , it is necessary to keep it long enough, for example, one field period. In this embodiment, an OR gate is used as the arithmetic circuit, and the logic is either negative logic or positive logic. A known circuit may be used as appropriate depending on the output of the second discrimination circuit.
発明の効果
以上のように本発明の非標準信号判別回路は、水平同期
信号の時間軸変動がいかなるものであっても、色副搬送
波の位相検出のみできわめて安定な非標準信号判別を行
なう。また、ディジタルＩＣで簡単に構成でき、時間軸
調整も不要なことからも実用上きわめて有利なものであ
る。Effects of the Invention As described above, the non-standard signal discriminating circuit of the present invention performs extremely stable non-standard signal discriminating only by detecting the phase of the color subcarrier, no matter what the time axis fluctuation of the horizontal synchronizing signal. Furthermore, it is extremely advantageous in practice because it can be easily constructed using a digital IC and does not require time axis adjustment.
第１図は本発明の一実施例の非標準信号判別回路の構成
を示すブロック図、第２図、第３図は標準信号入力時の
同非標準信号判別回路の動作を説明するためのタイミン
グ図、第４図は非標準信号入力時の同非標準信号判別回
路の動作を説明する２、４，１４．１６・・・・・・Ｄ
フリップフロップ、ａ 、 １８−・−・・ＥＸＣＬＵ
ＳＩＶＥ−ＯＲ／７’ −ト、８，２０・・・・・・リ
ドリガーモノマルチ、１１・・・・・・モノマルチ、２
２・・・・・・ＯＲゲート。
代理人の氏名 弁理士 中 尾 敏 男 ほか１名第２
図
第３図
一−］−−−ｒ１
判り）已カ ニ・−ニー−ルー−二ミー一・□−□
−第４図
１９１七ｒｌＪａろカーーーーーーーーーーーーーーー
ーーー−ｍ−−Ｌ″ 晶FIG. 1 is a block diagram showing the configuration of a non-standard signal discriminating circuit according to an embodiment of the present invention, and FIGS. 2 and 3 are timing diagrams for explaining the operation of the non-standard signal discriminating circuit when a standard signal is input. 2, 4, 14.16...D
Flip-flop, a, 18-...EXCLU
SIVE-OR/7'-to, 8, 20... Ridriger mono multi, 11... Mono multi, 2
2...OR gate. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 3 Figure 1-] ---r1 (understand)
-Figure 4 1917rlJarocar---m--L'' Akira
Claims (1)
号と色副搬送波の位相差を検出する第１の検出回路およ
び連続する水平期間の色副搬送波の位相関係が一定であ
るか否かを検出する第１の判別回路を有する第１の回路
と、１水平期間毎の水平同期信号と色副搬送波の位相差
を前記第１の回路の色副搬送波位相検出位置と異なる位
置で検出する第２の検出回路および連続する水平期間の
色副搬送波の位相関係が一定であるか否かを検出する第
２の判別回路を有する第２の回路と、前記第１の回路と
前記第２の回路の出力を入力し、前記第１および第２の
回路からともに色副搬送波の位相関係が一定でないこと
を示す信号が入力されたとき非標準信号判別信号を出力
する演算回路と非標準信号判別回路。A first detection circuit detects a phase difference between a horizontal synchronizing signal and a color subcarrier in each horizontal period of an NTSC color video signal, and detects whether the phase relationship between the color subcarriers in consecutive horizontal periods is constant. a first circuit having a first discrimination circuit; and a second circuit that detects a phase difference between a horizontal synchronizing signal and a color subcarrier for each horizontal period at a position different from the color subcarrier phase detection position of the first circuit. a second circuit having a detection circuit and a second discrimination circuit for detecting whether a phase relationship between color subcarriers in consecutive horizontal periods is constant; outputs of the first circuit and the second circuit; and a non-standard signal discriminating circuit that outputs a non-standard signal discriminating signal when a signal indicating that the phase relationship of the color subcarriers is not constant is input from the first and second circuits.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62276135A JP2595570B2 (en) | 1987-10-30 | 1987-10-30 | Non-standard signal discrimination circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62276135A JP2595570B2 (en) | 1987-10-30 | 1987-10-30 | Non-standard signal discrimination circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01117592A true JPH01117592A (en) | 1989-05-10 |
| JP2595570B2 JP2595570B2 (en) | 1997-04-02 |
Family
ID=17565270
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62276135A Expired - Fee Related JP2595570B2 (en) | 1987-10-30 | 1987-10-30 | Non-standard signal discrimination circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2595570B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0411661A2 (en) * | 1989-08-04 | 1991-02-06 | Matsushita Electric Industrial Co., Ltd. | Dot crawling interference elimination device and color subcarrier vertical correlation detection device |
| US6383464B1 (en) * | 1995-06-02 | 2002-05-07 | Owens Corning Fiberglas Technology, Inc. | Method for reducing sulfur-oxide emissions from an asphalt air-blowing process |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63126386A (en) * | 1986-11-17 | 1988-05-30 | Hitachi Ltd | Non-standard signal detecting circuit |
-
1987
- 1987-10-30 JP JP62276135A patent/JP2595570B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63126386A (en) * | 1986-11-17 | 1988-05-30 | Hitachi Ltd | Non-standard signal detecting circuit |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0411661A2 (en) * | 1989-08-04 | 1991-02-06 | Matsushita Electric Industrial Co., Ltd. | Dot crawling interference elimination device and color subcarrier vertical correlation detection device |
| US6383464B1 (en) * | 1995-06-02 | 2002-05-07 | Owens Corning Fiberglas Technology, Inc. | Method for reducing sulfur-oxide emissions from an asphalt air-blowing process |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2595570B2 (en) | 1997-04-02 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |