CN201812472U

CN201812472U - Device for separating cathode ray tube from video amplifier circuit

Info

Publication number: CN201812472U
Application number: CN2010201103977U
Authority: CN
Inventors: 黎望怀
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-02-09
Filing date: 2010-02-09
Publication date: 2011-04-27
Anticipated expiration: 2020-02-09

Abstract

The utility model relates to a device for separating a cathode ray tube (CRT) from a video amplifier circuit in equipment with CRT, such as color TVs, display devices and the like. All components (5) of the video amplifier circuit are mounted at a video amplification part (4) of a main board (6), then connected with a CRT socket (2) through a connecting lead (3) and inserted at the tail part of a CRT (1). By the adoption of the wide-band video amplifier circuit with strong load-carrying capacity, the R/G/B primary color signals outputted from a decoder are transmitted to a first-stage preamplifier for voltage amplification, then transmitted to a push-pull emitter follower for power amplification, and finally transmitted to the three cathodes of the CRT through the connecting lead (3). The utility model solves the problem of image white streaks caused by the long connecting wire (less than or equal to 2 m) for outputting the R/G/B primary color signals at the last stage of video amplification, prolongs the service life of the CRT socket and other elements, reduces the failure rate of the CRT, and facilitates the teaching and training of CRT equipment.

Description

The device that kinescope separates with video amplifier circuit

Affiliated technical field

The utility model relates to colour television set, computer monitor, video monitoring equipment and related experiment, the practice-training teaching of a kind of employing color picture tube (CRT) and examines the device that kinescope separates with video amplifier circuit in the equipment such as worker.

Background technology

At present, all adopt colour television set, computer monitor and other video monitoring and the practice-training teaching of CRT and examine construction equipment, and the afterbody of its kinescope all is connected to one and looks and put plate, is commonly called as " tailgate ", usually all with the primary colours matrix with look and put final circuit all

Be installed on its tailgate, partly link to each other with video decode on the mainboard by connecting line lead-in wire then.

Because final stage video amplifier circuit is operated in high voltage, high-power magnifying state, power consumption is bigger, components and parts such as base are damaged easily, simultaneously, also may cause in maintenance process, making accidentally kinescope to damage, and as being used for practice-training teaching and the colour television set operator's console of examining the worker, teaching and real training operation for convenience, require so especially, if kinescope can be separated with video amplifier circuit, that is just even more ideal.

But design both domestic and external all is the same, fails to break through this problem, found through experiments, if kinescope is separated with video amplifier circuit, the words of connecting line lengthening can cause that the phenomenon of white smear appears in image, and connecting line is long more, and conditions of streaking is obvious more.

Summary of the invention

In order to solve that the existing kinescope that contains colour television set, computer monitor and other video monitoring equipment of CRT must closely link together with video amplifier circuit and base serviceable life of bringing is short, cause the problem of kinescope damage during maintenance, and the needs of actual product requirement, for this reason, the improvement design of carrying out kinescope is separated with video amplifier circuit.

The technical scheme that its technical matters that solves the utility model adopts is:

1. comprise looking and put final circuit, mainboard, connection lead-in wire, base, kinescope composition.Wherein look whole elements of putting final circuit and all be installed in looking of a mainboard and put part, link to each other with base and be inserted in the afterbody of kinescope by connecting lead-in wire then.The tristimulus signals of colour decoder output can be modulated by connecting on the negative electrode that is added to the kinescope correspondence respectively that goes between, other pin also is directly to be added on the kinescope by going between, and can reach the design that kinescope separates with video amplifier circuit.

2. look and put final circuit and comprise that forward voltage amplifying circuit, broadband recommend emitter follower and form.The forward voltage amplifying circuit comprises looking to be put pipe, base stage and connects biasing resistor, collector and connect pull-up resistor, emitter and connect direct current negative feedback resistor, diode, emitter and connect high-frequency compensation resistance, electric capacity, be the strong broadband video amplifier circuit of a kind of carrying load ability, the tristimulus signals of colour decoder output can be carried out voltage amplification through one-level is preposition; Broadband is recommended emitter follower and is comprised repeating resistance, coupling capacitance, recommends to look and put pipe, isolation resistance, thereby carry out power amplification, the output negative pole tristimulus signals, the negative electrode that is sent to kinescope is respectively modulated again, solves to separate the back owing to tristimulus signals output connecting line lengthening causes that the phenomenon of white smear appears in image.

The beneficial effects of the utility model are, solved the problem that kinescope and video amplifier circuit must closely link together in the existing equipment that contains CRT, thereby strengthen the CRT base serviceable life, reduce the kinescope probability of damage, solved simultaneously and separated the back and cause that the phenomenon of white smear appears in image because tristimulus signals output connecting line extends.

Description of drawings

Below in conjunction with drawings and Examples the utility model is further specified.

Fig. 1 is a separate design effect structure synoptic diagram of the present utility model;

Fig. 2 is the strong broadband video amplifier circuit principle schematic of the utility model carrying load ability;

1. kinescopes among Fig. 1,2. base 3. connects lead-in wire,

4. look and put part, 5. video amplifier circuit element, 6. circuit main board

Each components and parts is as shown in table 1 among Fig. 2

Table 1:

Embodiment

As shown in Figure 1: whole elements (5) of video amplifier circuit all are installed in looking of a mainboard (6) and put part (4), and linking to each other with base (2) by connection lead-in wire (3) then is inserted in the afterbody of kinescope (1).

Red primary video amplifier circuit as shown in Figure 2, V1 is put pipe for looking among the figure, and R3, R4 are the base biasing resistor of V1, make it be operated in the common emitter magnifying state, carry out voltage amplification, and simultaneously, R3 also plays buffer action; Constitute emitter direct current negative-feedback circuit by R6, VD1, be used for stablizing the quiescent point of V1, wherein VD1 is provided with in order to improve the emitter current potential; Form the emitter peaking circuit by R7, C3; R5 is a collector load resistor; R1, R2, C1, C2 form to look puts the 180V electric source filter circuit, and 180V is through current-limiting resistance R1, after C1, the C2 filtering, adds to through collector load resistor R5 and to look the collector of putting pipe V1; Recommend emitter follower by the broadband that V2, V3 form, be coupled through R9, C6 from the R primary colour signal of V1 collector output, deliver to the base stage of V2, V3, after carrying out power amplification, output still is negative polarity R primary colour signal, and then, be sent to the R negative electrode of kinescope by connection lead-in wire (3) and modulate through isolation resistance R11.

Through experimental results show that: even output lead (3) lengthening (≤2m) can not influence its output effect yet, image can not produce the phenomenon of white smear.Other is green, blue primary is identical with the design of red primary.

Claims

1. device that kinescope separates with video amplifier circuit, comprise looking and put final circuit (5), mainboard (6), connection lead-in wire (3), base (2), kinescope (1), it is characterized in that: the described whole elements of putting final circuit of looking all are installed in looking of a mainboard and put part (4), link to each other with base and are inserted in the afterbody of kinescope by connecting lead-in wire then.

2. the device that kinescope according to claim 1 separates with video amplifier circuit, it is characterized in that: described looking put final circuit (5) and comprised the forward voltage amplifying circuit, broadband is recommended emitter follower, the forward voltage amplifying circuit comprises looking puts pipe (V1), base biasing resistor (R3, R4), collector load resistor (R5), emitter direct current negative feedback resistor (R6), diode (VD1), emitter peaking resistance (R7), electric capacity (C3), broadband are recommended emitter follower and are comprised repeating resistance R9, coupling capacitance (C6), recommend to look and put pipe (V2, V3), isolation resistance (R11).