KR930015758A

KR930015758A - Strong field quality compensation system

Info

Publication number: KR930015758A
Application number: KR1019910025676A
Authority: KR
Inventors: 심재경
Original assignee: 강진구; 삼성전자 주식회사
Priority date: 1991-12-31
Filing date: 1991-12-31
Publication date: 1993-07-24

Abstract

지역특성에 따른 전계강도의 변화를 고려하여 드레쇼율드 전압 레벨 이상의 RF 전계가 입력될 때에도 양질의 화면을 얻을 수 있도록 한다.Considering the change of the electric field strength according to the local characteristics, it is possible to obtain a good quality screen even when the RF field above the threshold voltage level is input.

튜너블록(8)에서는 안테나로 유입된 RF 신호를 IF 신호로 변환하여 통상적으로 복조블록(40)에 인가하여 복조블록(40)에서는 인가된 IF 신호로부터 비디오/오디오 신호를 분리하여 RF 변조기(30)의 비디오/오디오 신호 입력단에 인가하여 RF 변조기(30)에서는 주파수 변조에 의하여 변조(B+)와 TV출력으로 출력한다.In the tuner block 8, the RF signal introduced into the antenna is converted into an IF signal, and is typically applied to the demodulation block 40. In the demodulation block 40, the video / audio signal is separated from the applied IF signal. Is applied to the video / audio signal input terminal, and the RF modulator 30 outputs the modulation (B +) and TV output by frequency modulation.

이때, 복조블록(40)의 복조 IC(11)에서는 튜너블록(8)으로 피드백되는 RF AGC 전압을 비교기(18)의 V1에 인가하며 비교기(18)에서는 비교값 V1 V2일 경우 트랜지스터(19)의 베이스에 로우신호가 인가되어 항상 일정한 이득을 얻도록 하여 마이콤(20)의 A단자에 인가하며 마이콤(20)에서는 인가된 전압이 드레쇼율드 전압 이하일 경우는 장전계이므로 마이콤(20)의 제어신호에 의해 스위치 블록(21)을 오프시킴과 동시에 부스터(B+)를 오프시키도록 구성되었다.At this time, the demodulation IC 11 of the demodulation block 40 applies the RF AGC voltage fed back to the tuner block 8 to V1 of the comparator 18 and the comparator 18 when the comparison value V1 V2 is the transistor 19. A low signal is applied to the base of the microcomputer 20 so that a constant gain is always applied to the terminal A of the microcomputer 20. The microcomputer 20 controls the microcomputer 20 because the applied voltage is less than the dressing voltage. The switch block 21 is turned off by the signal and the booster B + is turned off at the same time.

Description

Strong field quality compensation system

본 내용은 요부공개 건이므로 전문내용을 수록하지 않았음As this is a public information case, the full text was not included.

제1도는 본 발명의 강전계 화질 보상을 위한 회로도, 제2도는 채널별 전계 강도에 따른 RF 자동이득 제어되는 피드백 전압변화표, 제3도는 FR 전계강도와 튜너전원 이득에 따른 특성도, 제4도는 각 채널별 드레쇼울드 전압을 나타낸 도면이고, 제5도는 마이콤의 플로우 챠트이다.1 is a circuit diagram for compensating for the strong electric field quality of the present invention, FIG. 2 is a feedback voltage variation table controlled by RF automatic gain control according to electric field strength for each channel, FIG. 3 is a characteristic diagram according to FR field strength and tuner power gain, and FIG. It is a figure which shows the threshold voltage for each channel, and FIG. 5 is a flowchart of a microcomputer.

Claims

The first amplifier 1 and the second amplifier 2 for amplifying a predetermined amount of the frequency signal flowing into the antenna in order to obtain a good quality screen by compensating for an abnormal symptom according to the change in electric field strength by using the RF AGC voltage. And a tuner block 8 for generating an IF signal from the output of the first amplifier 1 and the RF signal of the external signal input terminal E, and the IF output signal of the tuner block 8 A demodulation block 40 for separating an audio signal, an RF modulator 30 for modulating and outputting an output signal of the demodulation block 40, and a first amplifier 1 and a second amplifier 2 The microcomputer 20 for controlling the switch block 21 and the A terminal of the microcomputer 20 are connected to the tuner block 8 from the demodulation IC 11 of the demodulation block 40 according to the RF AGC voltage. Comparators 18 for turning on and off the transistor 19, characterized in that Quality rewards the strong field system.

The demodulation block 40 according to claim 1, further comprising: an IF amplifier (9), a small filter (10), a demodulation IC (11), a video detector (12), and a video picking signal. And a high pass filter (14) and a limiter (15) and an FH detection (16) at the output terminal of the demodulation IC (11) and the demodulation IC (11).

※ Note: The disclosure is based on the initial application.