CN2085122U

CN2085122U - Video and audio switching switch

Info

Publication number: CN2085122U
Application number: CN 90213012
Authority: CN
Inventors: 傅冠银; 徐雪娥
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-06-14
Filing date: 1990-06-14
Publication date: 1991-09-18

Abstract

The utility model relates to a novel video and audio switching switch composed of a control circuit, a synchronous separating circuit, a video switching circuit and an audio switching circuit. Field synchronizing signals generated by the synchronous separating circuit are sent to the control circuit, and then the output signals of the control circuit are sent to the video switching circuit and the audio switching circuit to be used for controlling the saturation or the cutoff of an audion, and the goal of selecting some video frequency and the corresponding audio signals is obtained. The switch has simpler circuit and structure and lower manufacturing cost than the Japanese VCS-500 video switch, but the switch has the functions of VCS-500 and can replace VCS-500 to be used on the aspects of television transmission, broadcasting control, the production of the television program, etc.

Description

Video and audio switching switch

The utility model can be used for the making of transmission of television, Broadcast Control, TV programme.

The purpose of this utility model provides a kind of device that replaces the VCS-500 of Sony Corporation's production.The used video/audio diverter switch of each TV station all is the VCS-500 of Sony Corporation now, costs an arm and a leg, but also wants foreign exchange, and this is unfavorable to the development of tv undertakings under the situation of current economic retrechment; Moreover, the function of the VCS-500 of this import is that general switch does not possess this function, so be necessary to design a kind of economic, practical novel switched replacement VCS-500 field blanking interval TV signal is switched, can save foreign exchange like this, foreign exchange is used in useful place.

The utility model is mainly partly formed by four: control circuit, synchronizing separator circuit, video switch circuit, frequency switch circuit.

Schematic diagram of the present utility model such as Fig. 1.Principle is as follows: deliver to control circuit by the isolated field sync signal of synchronizing separator circuit, produce a control signal by control circuit, this control signal is delivered to video switch circuit and frequency switch circuit, make two commutation circuits select one tunnel vision signal and corresponding audio signal.

Below from several aspects explanation the utility model:

1, separated in synchronization: synchronizing separator circuit of the present utility model is made of integrated package 74LS221 and 74LS74, resistance R 13, R14, and this circuit is separated the field sync signal in the composite synchronizing signal, and the CP place that delivers to control circuit is as clock pulse.Composite synchronizing signal is imported from the A point.Used each pin of integrated package marks in Fig. 1.

2, control circuit: control circuit of the present utility model is by d type flip flop D1, D2, D3, D4, D5; Multiselect one K switch 11, K21, K31, K41, K51; K switch 12, K13, K22, K23, K32, K33, K42, K43, K52, K53 constitute, and the output equation of trigger is Qn+1=Dn, and Q is an output signal, and D is an input signal, and n is a reset condition, and n+1 is a new state.With the CP pulse of field sync signal as five triggers.Fig. 2 is CP pulse, i.e. field sync signal.Fig. 3 is the waveform by the signal that break-make produced of multiselect one switch.Fig. 4 is the signal output waveform of trigger.When multiselect one switch choose wherein a road, suppose it is the first via, just the first via disconnects by closing, its waveform such as Fig. 3.Be not difficult to find out, even before second field pulse arrives, selected the first via, the output of d type flip flop also only just becomes high level when second field pulse arrives, therefore we just can control ending of triode or different logical with this variation of d type flip flop output, reach the purpose of selecting one road signal.D type flip flop could be exported high level when blanking pulse lock-out pulse arrival just simultaneously.The output signal of trigger D1, D2, D3, D4, D5 is delivered to BG6, BG7, BG8, BG9, the BG10 of video switch circuit BG1, BG2, BG3, BG4, BG5 and frequency switch circuit, uses K13, K23, K33, K43, K53 to D1, D2, D3, D4, D5 reset certainly before using.As if being the second tunnel disconnection (being that K21 disconnects) before selecting the first via, then select after the first via, it is output as " 0 " because of importing the end change for D3, D4, D5, and to the second the tunnel, Dn=" 0 " is so Qn+1=" 0 ".Ground connection when switch closes promptly connects power supply after the disconnection.

3, video switch circuit: video switch circuit of the present utility model is by triode BG1, BG2, BG3, BG4, BG5; Resistance R 1, R2, R3, R4, R5, R6; Capacitor C 1, C2, C3, C4, C5, C6 constitute.Wherein by C1, C2, C3, C4, C5 input, by C6 outputting video signal, respectively deliver to BG1, BG2, BG3, BG4, BG5 on respectively by the output signal of control circuit for five tunnel vision signals.As shown in Figure 4, if select the first via, then triode BG1 just just becomes saturation conduction by ending at black-out intervals in second blanking pulse arrival, thereby BG1 has video output.Simultaneously because D2, D3, D4, D5 are output as " 0 ", so BG2, BG3, BG4, BG5 end, thereby have only BG1 that video output is arranged, reached the purpose of selecting the first via at blanking interval, the rest may be inferred by analogy.

4, frequency switch circuit: frequency switch circuit of the present utility model is by triode BG6, BG7, BG8, BG9, BG10; Resistance R 7, R8, R9, R10, R11, R12; Capacitor C 7, C8, C9, C10, C11, C12 constitute, and the principle of frequency switch circuit is identical with the principle of video switch circuit.Wherein audio signal is exported from C12 from C7, C8, C9, C10, C11 input.BG6, BG7, BG8, BG9, BG10 are delivered in the output of D1, D2, D3, D4, D5 respectively.

In a word, the utility model circuit structure is simple, and cost is low, and is economical and practical, can replace the VCS-500 video/audio diverter switch of Sony Corporation and is used for transmission of television, Broadcast Control and television program designing, so have bigger using value.

Claims

1, a kind of novel video/audio diverter switch is characterized in that: it comprises control circuit, synchronizing separator circuit, video switch circuit, this four part of frequency switch circuit.

2, video/audio diverter switch according to claim 1 is characterised in that: control circuit is by trigger D1, D2, D3, D4, D5; Multiselect one switch, K11, K21, K31, K41, K51; Formations such as K switch 12, K13, K22, K23, K32, K33, K42, K43, K52, K53, and with the CP pulse of field sync signal as each trigger.

3, video/audio diverter switch according to claim 1 is characterised in that: synchronizing separator circuit is by integrated package 74LS221 and 74LS74, and resistance R 13, R14 constitute, and its effect is to isolate field sync signal from composite synchronizing signal.

4, video/audio diverter switch according to claim 1 is characterised in that: video switch circuit is by triode BG1, BG2, BG3, BG4, BG5, capacitor C 1, C2, C3, C4, C5, C6; Resistance R 1, R2, R3, R4, R5, R6 constitute, and the emitter of five triodes connects together.

5, be characterised in that according to the video/audio diverter switch described in the claim 1: it is by triode BG6, BG7, BG8, BG9, BG10; Capacitor C 7, C8, C9, C10, C11, C12; Resistance R 7, R8, R9, R10, R11, R12 constitute, and the emitter of five triodes connects together.