What parts are digital TVs made of

The TV is mainly composed of shell, picture tube, bottom plate, power supply, high-frequency head, image amplifier, video amplifier, decoding, brightness signal, line field, CPU, high voltage, etc.

The TV is mainly composed of high-frequency head, audio head, sound channel, common channel, synchronous scanning channel, color control display and power supply. Here's how it works.

The signal received from the antenna selects the high-frequency TV signal through the high-frequency head, and amplifies it, and then sends a fixed medium-frequency TV signal.

The common channel consists of an IF amplifier, a geophone, an amplifier, and a picture tube. The IF amplifier amplifies the IF signal from the high-frequency head to a sufficient amplitude, detects the IF carrier through the detector, restores the image signal, and transforms the second IF signal. The image signal is amplified and sent to the cathode of emitting electrons in the picture tube to control the emphasis of the emitting electron beam of the picture tube, and the image can be displayed on the phosphor screen.

The classification is as follows: 1) Tube televisions. The main circuit of this type of television consists of 18 20 tubes (vacuum tubes).

Because the cathode of the electron tube needs to be heated to a certain extent before it can emit electrons and enter the working state. Therefore, the power consumption of tube TVs is very high, the phosphor screen is generally not large, and the whole machine is very heavy, and most of them are early products of TVs, which have been eliminated.

2) Transistor TV. Transistor TVs, also known as discrete component TVs, are composed of more than 50 transistors and diodes in the main circuit. The structure of the sail branch circuit is complex, so the Cha barrier rate is high.

Maintenance and commissioning are cumbersome. With the advancement of electronic technology and the renewal of products, such televisions have also been eliminated.

3) Integrated circuit televisions. The main circuits in the machine are integrated in one or several large-scale integrated circuits, and the functions are becoming more and more complete to meet the needs of users in various aspects. Integrated circuit televisions can be divided into three types: four-chip, two-chip and single-chip.

Summary. The commonly used accessories of TV are: power board, backlight board, motherboard, logic board, LCD screen, chassis, picture tube, deflection coil, high-voltage package, high-frequency head, microprocessor, intermediate frequency processing manifold block, input signal selection switching manifold block, line, field scanning and color decoding and other small signal processing blocks, accompaniment power amplifier manifold blocks, speakers, switching power supply fast, line tubes, field output manifold blocks, sight release tubes, various high and low frequency small power tubes, various electrolytic capacitors, various dielectric capacitors, various resistors with different power and different resistance values, Various input and output interfaces, etc.

The common accessories of TV are: power board, backlight board, motherboard, logic board, LCD screen, chassis, picture tube, deflection coil, high-voltage package, high-frequency head, micro return limb processor, intermediate frequency processing manifold block, input signal selection switching manifold block, line, field scanning and color decoding and other small signal processing blocks, sound amplifier manifold blocks, speakers, switching power supply fast, line tubes, field hungry hand output manifold blocks, video release tubes, various high and low frequency small power tubes, various electrolytic capacitors, various dielectric capacitors, All kinds of resistors with different power and different resistance values, various input and output interfaces, etc.

The TV is mainly composed of high-frequency head, accompanying audio head, accompanying sound channel, public channel, scanning channel with sock bucket step, color control display and power supply. Its working principle is as follows: the signal received from the antenna is selected by the high-frequency head, and amplified by the high-frequency head, and then a fixed medium-frequency TV signal is sent.

They can be divided into three parts: the back cover of the chassis, the front panel, the middle frame and the picture tube, etc., the main printed base plate (core) and various components.

Whether it is a color TV or a black and white TV, its chassis is generally composed of three parts: the front panel (front frame), the middle frame and the back cover.

In conventional maintenance work,The front panel and the middle frame do not have to be disassembled,Only the back cover needs to be removed for general maintenance operations,So the front panel and the middle frame of some TVs are made into a whole。

The cable television system consists of three parts: the front end, the trunk system and the distribution system.

Antennas, satellite TV receivers, video recorders and other signal sources that receive open-circuit television signals are not unique to cable television, so they cannot be regarded as part of cable television systems.

The front-end is responsible for the processing of the signal. For satellite TV receivers, video recorders, etc., the output of the audio signal is modulated, modulated into a high-frequency signal of a certain channel, or first modulated into an intermediate frequency and then processed by the intermediate frequency and then upconverted into a high-frequency signal;The received open-circuit TV signal can be directly amplified or demodulated into an audio-visual signal and then modulated, or it can be directly downconverted into an intermediate frequency after intermediate frequency processing and then upconverted into a high-frequency signal. The processed TV high-frequency signals are also mixed by the front end and output to the trunk system.

The trunk system is responsible for the transmission of signals, and it should be pointed out that the branch lines also include the early knowledge of the air in the trunk system. The trunk line system consists of trunk cables, branch cables, trunk amplifiers and distributors, branch devices, etc., and will also use optical fiber rocks or microwaves for long-distance transmission.

The distribution system is responsible for assigning signals to each user. It is composed of distribution amplifier, distributor, brancher, branch cable, user brancher, serial unit, user cable, user box, etc.

Take CRT, for example.

1 shell, well understood.

2 CRT, also very well understood.

3 plates, which contain the following circuits:

Power supply, high-frequency head, image amplifier, video amplifier, decoding, brightness signal, line field, CPU, high voltage, etc.

The most basic parts are resistors, capacitors, and semiconductor display plastic shells.

The circuitry of the TV is also divided into color and black and white.

Color television must contain the basic components of black and white television, and at present, color television systems in all countries of the world can be compatible with black and white television in that country. Therefore, a color television must contain the basic parts of a black-and-white television set, i.e., a common channel, a sound channel, and a line and field scanning system. Unlike black-and-white televisions, decoders are used instead of image channels, as well as auxiliary circuitry necessary for color picture tubes.

The TV is composed of a display, a motherboard, a case, a panel button and a remote control, and the motherboard is an electronic circuit composed of many transistors, integrated circuits, resistors, capacitors and other electronic components

Enclosures, CRTs, power supplies and motherboards.

Power supply part, driver board, high voltage board, and TV board.

The power supply is the power supply, and the mains power is converted to 12V LCD TV working voltage; The high-voltage board boosts the high-voltage AC from 12V to 1500 1800V, which is used to light the CCFL backlight of the panel; The driver board is the TFT that drives the control liquid crystal and is used to display the signal. It is mainly composed of panel control logic, brightness control logic, DC to DC conversion logic, transmission of TTL level signal to LCD display module circuit, etc.; The TV board is the part that receives, demodulates, and decodes the TV signal.