JPS5942518B2 - signal control circuit - Google Patents

signal control circuit

Info

Publication number
JPS5942518B2
JPS5942518B2 JP51157230A JP15723076A JPS5942518B2 JP S5942518 B2 JPS5942518 B2 JP S5942518B2 JP 51157230 A JP51157230 A JP 51157230A JP 15723076 A JP15723076 A JP 15723076A JP S5942518 B2 JPS5942518 B2 JP S5942518B2
Authority
JP
Japan
Prior art keywords
signal
level
control circuit
amplifier
control
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
Application number
JP51157230A
Other languages
Japanese (ja)
Other versions
JPS5380132A (en
Inventor
登史 岡田
和男 山極
勉 新村
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sony Corp
Original Assignee
Sony Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sony Corp filed Critical Sony Corp
Priority to JP51157230A priority Critical patent/JPS5942518B2/en
Priority to AU31998/77A priority patent/AU3199877A/en
Priority to DE19772757792 priority patent/DE2757792A1/en
Priority to FR7739146A priority patent/FR2375757A1/en
Priority to NL7714446A priority patent/NL7714446A/en
Publication of JPS5380132A publication Critical patent/JPS5380132A/en
Publication of JPS5942518B2 publication Critical patent/JPS5942518B2/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G3/00—Gain control in amplifiers or frequency changers without distortion of the input signal
    • H03G3/20—Automatic control
    • H03G3/30—Automatic control in amplifiers having semiconductor devices
    • H03G3/3036—Automatic control in amplifiers having semiconductor devices in high-frequency amplifiers or in frequency-changers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L7/00—Automatic control of frequency or phase; Synchronisation
    • H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/44—Colour synchronisation
    • H04N9/455—Generation of colour burst signals; Insertion of colour burst signals in colour picture signals or separation of colour burst signals from colour picture signals
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/64—Circuits for processing colour signals
    • H04N9/68—Circuits for processing colour signals for controlling the amplitude of colour signals, e.g. automatic chroma control circuits

Description

【発明の詳細な説明】 録画再生機などから得られるカラー映像信号中の搬送色
信号はヘッドとテープとの当りむらなどによりレベル変
動を受けている。DETAILED DESCRIPTION OF THE INVENTION A color signal carried in a color video signal obtained from a recording/playback device or the like is subject to level fluctuations due to uneven contact between the head and the tape.

このため、受像機の搬送色信号の伝送系には、いわゆる
ＡＣＣ回路が設けられ、搬送色信号のレベルが一定にな
るようにされている。即ち、第１図は、従来のＡＣＣ回
路を示すもので、バンドパスアンプ１にて取り出された
搬送色信号が利得制御アンプ２１を通じて復調器２及び
３に供給され、またアンプ２１を通じて搬送色信号がバ
ーストゲート回路２２に供給されてバースト信号が取り
出され、これが同期検波回路２３に供給されてＡＰＣ回
路より得られる色副搬送波信号にて同期検波され、その
検波電圧がレベル比較器２４において一定レベルＳと比
較され、その差の電圧がローパスフィルタ２５を通じて
利得制御アンプ２１に供給されてその利得が制御される
。For this reason, a so-called ACC circuit is provided in the transmission system of the carrier color signal of the receiver to keep the level of the carrier color signal constant. That is, FIG. 1 shows a conventional ACC circuit, in which a carrier color signal extracted by a bandpass amplifier 1 is supplied to demodulators 2 and 3 through a gain control amplifier 21, and a carrier color signal is outputted through the amplifier 21. is supplied to the burst gate circuit 22 to extract a burst signal, which is supplied to the synchronous detection circuit 23 where it is synchronously detected using the color subcarrier signal obtained from the APC circuit, and the detected voltage is set at a constant level by the level comparator 24. The difference voltage is supplied to the gain control amplifier 21 through the low-pass filter 25 to control its gain.

バンドパスアンプ１から得られる搬送色信号のレベルは
一定レベルＳと変動分△の和としてＳ＋△と表わされ、
同期検波回路２３でこのレベルＳ＋△が検出され、レベ
ル比較器２４から一定レベルＳとの差即ち変動分△が取
り出され、そしてアンプ２１の利得が、変動分△が大き
いときは小さくなり、変動分△が小さいときは大きくな
るように制御されて、アンプ２１からの搬送色信号のレ
ベルが一定となるようにされる。しかしながら、この場
合、制御ループはいわゆる閉ループであつて、必ず制御
の誤差を伴い、従つて搬送色信号のレベルを常に一定に
することはできない。The level of the carrier color signal obtained from the bandpass amplifier 1 is expressed as S + △ as the sum of the constant level S and the variation △,
The synchronous detection circuit 23 detects this level S+△, and the level comparator 24 extracts the difference from the constant level S, that is, the variation Δ, and the gain of the amplifier 21 becomes smaller when the variation Δ is large. When the minute Δ is small, it is controlled to be large, so that the level of the carrier color signal from the amplifier 21 is kept constant. However, in this case, the control loop is a so-called closed loop, which inevitably involves control errors, and therefore the level of the carrier color signal cannot always be kept constant.

本発明は、上述のような信号制御回路において、制御の
誤差を確実に取り除くようにしたものである。The present invention reliably eliminates control errors in the signal control circuit as described above.

以下、第２図を参照しながら本発明の一実施例について
説明しよう。Hereinafter, one embodiment of the present invention will be described with reference to FIG.

この第２図において第１図と対応する部分には同一符号
を付し、その詳細説明は省略する。同図において、利得
制御アンプ２１からの搬送色信号を別の利得制御アンプ
５０を通じて復調器２及び３に供給するようにする。In FIG. 2, parts corresponding to those in FIG. 1 are designated by the same reference numerals, and detailed explanation thereof will be omitted. In the figure, the carrier color signal from the gain control amplifier 21 is supplied to the demodulators 2 and 3 through another gain control amplifier 50.

利得制御アンプ２１からの搬送色信号のレベルは一定レ
ベルＳと変動分Δの和としてＳ＋△′と表わされ、レベ
ル比較器２４からは、この変動分△′に応じた電圧△’
にが得られる。そして、このレベル比較器２４よりの電
圧△’にをアンプ５１に供給して、Ｓ利得制御アンプ５
０の利得を？にするようＱ．＋△′ な電圧を得、これを利得制御アンプ５０に供給する。The level of the carrier color signal from the gain control amplifier 21 is expressed as S+Δ' as the sum of a constant level S and a variation Δ, and the level comparator 24 outputs a voltage Δ' corresponding to this variation Δ'.
is obtained. Then, the voltage Δ' from the level comparator 24 is supplied to the amplifier 51, and the S gain control amplifier 5
A gain of 0? Q. +Δ' voltage is obtained and supplied to the gain control amplifier 50.

従つて、利得制御アンプ５０において、搬送色ご信号の
レベルは（Ｓ＋Δ）×？＝ＳとされＳ＋△す る。Therefore, in the gain control amplifier 50, the level of the carrier color signal is (S+Δ)×? =S and S+△.

即ち一定レベルとされる。なお、別の利得制御アンプ５
０を設けることなく、アンプ５１からの電圧を復調器２
及び３に供給して復調色信号のレベルを，倍にするよう
にしてもよい。In other words, it is set at a constant level. Note that another gain control amplifier 5
The voltage from the amplifier 51 is transferred to the demodulator 2 without providing 0.
and 3 to double the level of the demodulated color signal.

本発明は、また、録画再生機のＡＣＣ回路にも適用でき
る。The present invention can also be applied to an ACC circuit of a recorder/player.

上述のように、本発明によれば閉ループで構成された信
号制御回路の制御の誤差を完全に取り除くことができ、
ＡＣＣ回路に適用するときは色信号のレベルを確実に一
定にすることができる。As described above, according to the present invention, it is possible to completely eliminate control errors in a signal control circuit configured in a closed loop.
When applied to an ACC circuit, the level of the color signal can be reliably kept constant.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は従来の信号制御回路の一例の系統図、第２図は
本発明による信号制御回路の一例の系統図である。 １はバンドパスアンプ、２及び３は復調器、２１及び５
０は利得制御アンプ、２２はバーストゲート回路、２３
は同期検波回路、２４はレベル比較器、２５はローパス
フイルタである。FIG. 1 is a system diagram of an example of a conventional signal control circuit, and FIG. 2 is a system diagram of an example of a signal control circuit according to the present invention. 1 is a bandpass amplifier, 2 and 3 are demodulators, 21 and 5
0 is a gain control amplifier, 22 is a burst gate circuit, 23
24 is a level comparator, and 25 is a low-pass filter.

Claims (1)

【特許請求の範囲】[Claims] １ カラー映像信号よりバースト信号を取り出し、この
バースト信号と基準信号を比較し、その比較出力を利得
制御回路に供給して搬送色信号の大きさを制御するとと
もに、上記比較出力を用いて上記利得制御回路により制
御された信号の制御誤差を除去するようにした信号制御
回路。1 A burst signal is extracted from a color video signal, this burst signal is compared with a reference signal, and the comparison output is supplied to a gain control circuit to control the magnitude of the carrier color signal, and the comparison output is used to control the above gain. A signal control circuit that removes control errors in signals controlled by the control circuit.
JP51157230A 1976-12-24 1976-12-24 signal control circuit Expired JPS5942518B2 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
JP51157230A JPS5942518B2 (en) 1976-12-24 1976-12-24 signal control circuit
AU31998/77A AU3199877A (en) 1976-12-24 1977-12-23 T.v. colour hue regulation
DE19772757792 DE2757792A1 (en) 1976-12-24 1977-12-23 ARRANGEMENT FOR CONTROLLING A CERTAIN PARAMETER OF AN ELECTRICAL SIGNAL, IN PARTICULAR A COLOR MIXED SIGNAL
FR7739146A FR2375757A1 (en) 1976-12-24 1977-12-23 Electric signal parameter control device - includes control circuit with parameter setting circuit minimising its errors
NL7714446A NL7714446A (en) 1976-12-24 1977-12-27 DEVICE FOR REGULATION OF A PRE-DETERMINED PARAMETER OF AN ELECTRICAL SIGNAL.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP51157230A JPS5942518B2 (en) 1976-12-24 1976-12-24 signal control circuit

Publications (2)

Publication Number Publication Date
JPS5380132A JPS5380132A (en) 1978-07-15
JPS5942518B2 true JPS5942518B2 (en) 1984-10-15

Family

ID=15645066

Family Applications (1)

Application Number Title Priority Date Filing Date
JP51157230A Expired JPS5942518B2 (en) 1976-12-24 1976-12-24 signal control circuit

Country Status (5)

Country Link
JP (1) JPS5942518B2 (en)
AU (1) AU3199877A (en)
DE (1) DE2757792A1 (en)
FR (1) FR2375757A1 (en)
NL (1) NL7714446A (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56160189A (en) * 1980-04-29 1981-12-09 Sony Corp Differential gain compensating circuit
DE3123038A1 (en) * 1981-06-10 1982-12-30 Siemens AG, 1000 Berlin und 8000 München METHOD AND ARRANGEMENT FOR CONTROLLING THE DIGITAL CHROMINANCE SIGNAL OF A COLOR TELEVISION RECEIVER
DE3266503D1 (en) * 1982-05-27 1985-10-31 Itt Ind Gmbh Deutsche Integrated digital chrominance channel-circuit with controlled amplification
JPS6042996A (en) * 1983-08-19 1985-03-07 Matsushita Electric Ind Co Ltd Television receiver
JPS61137488A (en) * 1984-12-07 1986-06-25 Matsushita Electric Ind Co Ltd Chrominance signal processing device
GB2191367B (en) * 1986-05-29 1990-04-11 Rca Corp Circuitry for reducing demodulation phase error as for an automatic deghosting system

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1034695B (en) * 1955-02-25 1958-07-24 Siemens Ag Circuit arrangement for influencing, e.g. B. to keep the output voltage of an amplifier constant
FR1277350A (en) * 1960-10-18 1961-12-01 Thomson Houston Comp Francaise Phase correction device
FR1338766A (en) * 1962-11-07 1963-09-27 Ferguson Radio Corp Improvements to frequency stabilization devices
US3659040A (en) * 1968-09-30 1972-04-25 Victor Company Of Japan A control system for a color synchronizing signal oscillator in a magnetic recording and reproducing apparatus
US3585280A (en) * 1969-06-11 1971-06-15 Columbia Broadcasting Syst Inc Gain correction apparatus for color picture information signals reproduced from a record medium
US3918003A (en) * 1974-10-29 1975-11-04 Bell Telephone Labor Inc Combined feedback and feedforward automatic gain control

Also Published As

Publication number Publication date
DE2757792A1 (en) 1978-07-06
NL7714446A (en) 1978-06-27
AU3199877A (en) 1979-06-28
JPS5380132A (en) 1978-07-15
FR2375757A1 (en) 1978-07-21

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