KR940002755Y1 - High frequency band amplifying circuit for vcr - Google Patents
High frequency band amplifying circuit for vcr Download PDFInfo
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- KR940002755Y1 KR940002755Y1 KR2019890001994U KR890001994U KR940002755Y1 KR 940002755 Y1 KR940002755 Y1 KR 940002755Y1 KR 2019890001994 U KR2019890001994 U KR 2019890001994U KR 890001994 U KR890001994 U KR 890001994U KR 940002755 Y1 KR940002755 Y1 KR 940002755Y1
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/10009—Improvement or modification of read or write signals
- G11B20/10018—Improvement or modification of read or write signals analog processing for digital recording or reproduction
- G11B20/10027—Improvement or modification of read or write signals analog processing for digital recording or reproduction adjusting the signal strength during recording or reproduction, e.g. variable gain amplifiers
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/10009—Improvement or modification of read or write signals
- G11B20/10046—Improvement or modification of read or write signals filtering or equalising, e.g. setting the tap weights of an FIR filter
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/18—Error detection or correction; Testing, e.g. of drop-outs
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/24—Signal processing not specific to the method of recording or reproducing; Circuits therefor for reducing noise
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- 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
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- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Multimedia (AREA)
- Television Signal Processing For Recording (AREA)
Abstract
내용 없음.No content.
Description
제 1 도는 종래 브이씨알의 휘도신호재생처리 블록도.1 is a block diagram of a luminance signal regeneration process of a conventional VR.
제 2 도는 본 고안 브이씨알의 고역증폭회로도.2 is a high frequency amplification circuit of the V-seal of the present invention.
* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for main parts of the drawings
1,2 : 전치증폭기 3 : 스위칭회로부1,2: Preamplifier 3: Switching Circuit
4 : 색신호처리회로부 5 : 고역필터회로부4 color signal processing circuit 5 high frequency filter circuit
6 : 자동이득조절회로부 7 : 드롭아웃보상회로부6 automatic gain control circuit 7 drop-out compensation circuit
8 : 리미터회로부 9 : 에프엠복조기8: limiter circuit 9: FM demodulator
10, 10a : 디 엠파시스회로부 11 : 잡음경감회로부10, 10a: D emphasis circuit portion 11: Noise reduction circuit portion
12 : 색신호출력부 13 : 복합영상신호부12: color signal output unit 13: composite video signal unit
14 : 레벨검출회로부 R11-R16 : 저항14: level detection circuit section R11-R16: resistance
C11, C12 : 콘덴서 CP11, CP12 : 비교기C11, C12: Condenser CP11, CP12: Comparator
NM11 : 엔모스NM11: NMOS
본 고안은 브이씨알 재생신호의 고역증폭회로에 관한 것으로, 특히, 테이프의 장시간 사용에 의해 재생신호가 감쇄됨에 따라 디엠파시스회로의 고역특성을 개선하여 선명한 화상을 제공할 수 있게한 브이씨알의 고역증폭회로에 관한 것이다.The present invention relates to a high frequency amplification circuit of a V-CAL reproduction signal. In particular, the high-frequency amplification circuit of the V-CAL signal improves the high-frequency characteristics of the DMMP circuit as the reproduction signal is attenuated by long-term use of the tape. A high frequency amplifier circuit.
제 1 도는 종래의 휘도신호재생처리 블록도로서 이에 도시한 바와같이, 헤드로부터 출력되는 신호는 단자(CH1) 및 전치증폭기(1), 단자(CH2) 및 전치증폭기(2)를 각기 통해 30Hz신호가 인가되는 스위칭회로부(3)에 인가되어 연속된 하나의 신호로 합성된 후 색신호처리회로부(4) 및 고역필터회로부(5)의 입력측에 인가된다. 또, 상기 고역필터회로부(5)에 인가된 신호는 저역변환색신호가 제거되고, 다시 자동이득조절회로부(6)를 통해 이득이 조절된 다음 드롭아웃보상회로부(7)에 인가되어 드롭아웃이 보상되며, 또 리미터회로부(8)를 통해 진폭이 일정하게 된 후 에프엠복조기(9)에 인가되어 소정의 대역폭을 갖는 휘도신호로 출력되는데, 이 휘도신호는 디엠파시스회로부(10)를 통해 고역의 잡음성분이 경감되고, 잡음경감회로부(11)에 인가되어 휘도신호중의 잡음성분이 경감된 후, 색신호출력부(12)로부터 출력되는 색신호와 복합영상신호부(13)에서 혼합되게 되어 있었다.1 is a block diagram of a conventional luminance signal reproduction processing, as shown therein, a signal output from a head is a 30Hz signal through a terminal CH1, a preamplifier 1, a terminal CH2, and a preamplifier 2, respectively. Is applied to the switching circuit section 3 to be applied, synthesized into one continuous signal, and then applied to the input side of the color signal processing circuit section 4 and the high pass filter circuit section 5. In addition, the low frequency conversion color signal is removed from the high frequency filter circuit section 5, the gain is adjusted through the automatic gain control circuit section 6, and then applied to the dropout compensation circuit section 7 to compensate for the dropout. In addition, after the amplitude becomes constant through the limiter circuit unit 8, it is applied to the FM demodulator 9 and output as a luminance signal having a predetermined bandwidth. The noise component was reduced, applied to the noise reduction circuit section 11 to reduce the noise component in the luminance signal, and then mixed in the color signal output from the color signal output section 12 and the composite video signal section 13.
그러나 이와같은 처리방식은 테이프가 장시간 사용됨에 따라 헤드로부터 재생출력레벨이 감소되는 것을 자동이득조절회로부에서 보상하게 되는데, 이때 잡음성분도 함께 증폭되어 시청자에게 선명한 화상을 제공할 수 없는 문제점이 있었다.However, such a processing method compensates for the decrease in the reproduction output level from the head as the tape is used for a long time, and the automatic gain control circuit unit compensates for the noise.
본 고안은 이와같은 문제점을 해결하기 위하여 테이프가 장시간 사용되어 헤드의 출력레벨이 감소됨에 따라 디엠파시스회로부의 고역특성을 개선하여 재생신호의 경계부위를 강조함으로써 시청자에게 선명한 화상을 제공할 수 있는 회로를 안출한 것으로 이를 첨부된 도면에 의하여 상세히 설명하면 다음과 같다.In order to solve this problem, the tape can be used for a long time, and as the output level of the head is reduced, the high frequency characteristic of the DMP circuit can be improved to emphasize the boundary of the playback signal, thereby providing a clear image to the viewer. When the circuit is described in detail by the accompanying drawings as follows.
제 2 도는 본 고안 브이씨알의 고역증폭회로도로서 이에 도시한 바와같이, 헤드로부터 재생신호가 인가되는 단자(CH1), (CH2)가 전치증폭기(1), (2)를 각기 통해 스위칭회로부(3)의 입력측에 접속되고, 그 스위칭회로부(3)의 출력측이 고역필터회로부(5) 및 자동이득조절회로부(6), 드롭아웃보상회로부(7)를 통한 후 다시 리미터회로부(8) 및 에프엠복조기(9), 디엠파시스회로부(10), 잡음경감회로부(11)를 통해 복합영상신호부(13)에 접속된 휘도신호재생처리계에 있어서, 상기 고역필터회로부(5)의 출력측에 레벨검출회로부(14)를 접속하여 그 레벨검출회로부(14)의 출력측을 비반전입력단자에 기준전압(Vref)이 인가되는 비교기(CP11)의 반전입력단자측에 접속하고, 그 비교기(CP11)의 출력단자를 브이디알(Voltage Dependent Resistor)용 엔모스(NM11)의 게이트에 접속하여 드레인을 저항(R14) 및 콘덴서(C11)에 접속하며, 그 접속점을 비반전단자가 에프엠복조기(9)의 출력측에 접속된 비교기(CP12)의 반전입력단자에 접속하고, 이 비교기(CP12)의 출력단자를 디엠파시스회로부(10)의 입력측 및 병렬접속된 저항(R15) 및 콘덴서(C12)를 통해 상기 저항(R14) 및 이 비교기(CP12)의 반전입력단자 접속점에 공통접속하며 이 비교기(CP12)의 출력단자를 상기 잡음경감회로부(11)에 접속하여 구성한 것으로 이와같이 구성된 본 고안의 작용 및 효과를 상세히 설명하면 다음과 같다.2 is a diagram showing a high frequency amplification circuit of the inventive V-CAL. As shown therein, the terminals CH1 and CH2 to which a reproduction signal is applied from the head are respectively connected to the preamplifiers 1 and 2 through the switching circuit section 3. Is connected to the input side of the switching circuit section 3, and the output side of the switching circuit section 3 passes through the high pass filter circuit section 5, the automatic gain control circuit section 6, and the dropout compensation circuit section 7, and then the limiter circuit section 8 and the FM demodulator. (9), in the luminance signal reproduction processing system connected to the composite video signal unit 13 through the de-emphasis circuit unit 10 and the noise reduction circuit unit 11, the level detection at the output side of the high pass filter circuit unit 5; The circuit section 14 is connected, and the output side of the level detection circuit section 14 is connected to the inverting input terminal side of the comparator CP11 to which the reference voltage Vref is applied to the non-inverting input terminal, and the output of the comparator CP11 is connected. Connect the terminal to the gate of NMOS (NM11) for Voltage Dependent Resistor Is connected to the resistor R14 and the capacitor C11, and its connection point is connected to the inverting input terminal of the comparator CP12 whose non-inverting terminal is connected to the output side of the FM demodulator 9, and the output of this comparator CP12 is connected. The terminal is commonly connected to the resistor R14 and the inverting input terminal connection point of the comparator CP12 through an input side of the de-emphasis circuit unit 10 and a resistor R15 and a capacitor C12 connected in parallel. When the output terminal of the) is configured by connecting to the noise reduction circuit unit 11 will be described in detail the operation and effect of the present invention configured as described above.
헤드로부터 입력되는 재생신호는 전치증폭기(1, 2) 및 스위칭회로부(3), 고역필터회로부(5)를 통해 출력되는데, 이 고역필터회로부(5)의 출력측에 출력되는 신호의 레벨은 레벨검출회로부(14)에서 검출되어 비교기(CP11)의 반전입력단자에 인가된다. 여기서 이 비교기(CP11)의 비반전입력단자에 인가되는 기준전압(Vref)을 테이프를 소정시간이상 사용하였을때 상기 레벨검출회로부(14)의 출력측에 출력되는 전압과 같게 설정시켜 놓게되면, 테이프를 장시간 사용함에 따라 상기 레벨검출회로부(14)의 출력측에 출력되는 전위는 점차 낮아져 기준전압(Vref)보다 낮게되는 순간부터 이 비교기(CP11)의 출력단자에 고전위가 출력되어 브이디알용 엔모스(NM11)의 게이트에 인가된다. 여기서 상기 브이디알용 엔모스(NM11)는 게이트와 소오스간의 전위에 따라 드레인과 소오스간의 저항값이 변화되는 특성을 갖고 있으므로 테이프를 장시간 사용함에 따라 이 브이디알용 엔모스(NM11)의 드레인과 소오스간에 접속된 저항(R14)의 양단간 저항값이 점차 변화되므로 비교기(CP12)의 반전입력단자에 인가되는 전압도 이에따라 변화되어 결국, 디엠파시스회로부(10a)의 고역(3-4MHz)특성이 좋아지게 된다.The reproduction signal input from the head is output through the preamplifiers 1 and 2, the switching circuit section 3, and the high pass filter circuit section 5. The level of the signal output to the output side of the high pass filter circuit section 5 is level detected. It is detected by the circuit section 14 and applied to the inverting input terminal of the comparator CP11. When the reference voltage Vref applied to the non-inverting input terminal of the comparator CP11 is set to be equal to the voltage output to the output side of the level detection circuit unit 14 when the tape is used for a predetermined time, the tape is As a long time of use, the potential output to the output side of the level detection circuit unit 14 gradually decreases, and from the moment when it becomes lower than the reference voltage Vref, a high potential is output to the output terminal of the comparator CP11, thereby providing an enMOS for the VDL. Is applied to the gate of NM11). Here, the VDL NMOS 11 has a characteristic that the resistance value between the drain and the source is changed according to the potential between the gate and the source, and thus the drain and source of the VDL NMOS 11 is increased as the tape is used for a long time. Since the resistance value between both ends of the resistor R14 connected between the electrodes is gradually changed, the voltage applied to the inverting input terminal of the comparator CP12 is also changed accordingly, resulting in a good high frequency (3-4 MHz) characteristic of the DMP circuit unit 10a. You lose.
이상에서 상세히 설명한 바와같이 본 고안은 테이프가 장시간 사용되어 재생신호가 감쇄됨에 따라 디엠파시스회로의 고역특성을 개선하여 시청자에게 선명한 화상을 제공할 수 있는 이점이 있다.As described in detail above, the present invention has an advantage of providing a clear image to a viewer by improving the high frequency characteristic of the DMP circuit as the playback signal is attenuated by the tape being used for a long time.
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Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR2019890001994U KR940002755Y1 (en) | 1989-02-25 | 1989-02-25 | High frequency band amplifying circuit for vcr |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR2019890001994U KR940002755Y1 (en) | 1989-02-25 | 1989-02-25 | High frequency band amplifying circuit for vcr |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| KR900016177U KR900016177U (en) | 1990-09-03 |
| KR940002755Y1 true KR940002755Y1 (en) | 1994-04-23 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR2019890001994U KR940002755Y1 (en) | 1989-02-25 | 1989-02-25 | High frequency band amplifying circuit for vcr |
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| Country | Link |
|---|---|
| KR (1) | KR940002755Y1 (en) |
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1989
- 1989-02-25 KR KR2019890001994U patent/KR940002755Y1/en not_active IP Right Cessation
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| Publication number | Publication date |
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| KR900016177U (en) | 1990-09-03 |
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