Classification of TV sets?

Electron tube TV. The main circuit of this TV set consists of 18~20 electron tubes. Because the cathode of the electron tube needs to be heated to a certain extent to emit electrons and enter the working state. Therefore, electron tube TV consumes a lot of power, the screen is generally small, the whole machine is very heavy, and most of them are early products of TV sets, which have been eliminated.

(2) transistor TV. Transistor TV is also called discrete component TV. The main circuit of the whole machine consists of more than 50 transistors and diodes. The circuit structure is complex and the failure rate is high. Maintenance and debugging are troublesome. With the progress of electronic technology and the upgrading of products, such TV sets have also been eliminated.

(3) integrated circuit television. The main circuits in the machine are integrated in one or several large-scale integrated circuits, and their functions are becoming more and more perfect, meeting the needs of users in many aspects. Integrated circuit TV sets can be divided into four types, two types and one type.

2. Classification by function

(1) remote control color TV. Nowadays, all color TVs have remote control function. Compared with the old manual and mechanical tuning, it is more convenient to use and has more complete functions.

It allows viewers to operate the TV set within a certain distance, including switching on and off, selecting program channels, adjusting volume, brightness, color saturation and so on. In addition, it can automatically search and select channels, store and memorize multiple pre-selected channels (30 ~ 100 programs), and turn on and off at regular intervals.

(2) Color TV with karaoke function. A color TV with karaoke function can be equipped with a universal video recorder for karaoke singing.

(3) Video and color TV combination machine. In order to facilitate the recording, playing and karaoke singing of TV programs, some manufacturers have also produced video and color TV integrated machines to make them a whole.

3, according to the characteristics of the screen classification

CRT is the heart of TV and the most important device in TV. The fluorescent screen is the part of the cathode ray tube that displays images and is directly exposed outside the TV set. Classification according to the characteristics of fluorescent screens is simple, convenient and intuitive.

(1) is classified according to the colors reproduced on the fluorescent screen.

1) Black and white TV. The screen of this TV can only reproduce the brightness difference of the shooting scene and present black and white images.

2) color TV. This TV screen can not only reproduce the brightness difference of the shot scene, but also restore the hue and saturation of the shot scene, presenting a color image.

From the perspective of transmitting image information, color TV sets can transmit more information than black-and-white TV sets, reflect the actual situation of the original scenery more truly and vividly, and have more colorful expressive force.

(2) Classification by screen size. There are large and small TV screens, and people are used to using inches (diagonal size) to reflect their differences.

However, the expression of inch is sometimes inaccurate. For example, the diagonal size of a TV screen with the same size14 inch may be 35cm or 37cm, so in some technical data of the new standard, cm is directly used to represent the diagonal size. According to the diagonal size of the fluorescent screen, TV sets can be roughly divided into three categories: medium screen, large screen and super-large screen.

(3) According to the flatness of the fluorescent screen. In the past, most TV sets were ordinary spherical picture tubes, and the viewing angle range was relatively small due to the bending of the screen. The new generation of large-screen color TV sets mostly use "right-angle plane" and "super-plane" fluorescent screens, which increase the viewing angle and avoid picture distortion.

So there are some sayings such as "right-angle flat-panel color TV", "ultra-flat-panel color TV" and "flat-panel color TV", which mainly emphasize the characteristics of these color TVs in screen flatness.

(4) According to the aspect ratio of the fluorescent screen. Generally, the aspect ratio of TV screen is 4:3 or 5:4. With the successful development of high definition television (HDTV), widescreen TV sets have developed rapidly, and its aspect ratio is 16:9.

4, according to the signal processing classification.

According to signal processing methods, it can be divided into analog TV and digital TV. If analog TV signals (including image and audio signals) are converted into digital signals and then processed and transmitted in digital form, they must be received by digital TV sets.

After binary digital coding, the TV signal has stronger anti-interference ability than the original analog signal. Even after long-distance transmission and repeated recording, it can be recovered almost without distortion through balanced reproduction. Compared with analog TV, digital TV is easier to adjust and has higher reliability and stability.

Especially the application of VLSI, microprocessor and software makes the future digital TV production process simple, low cost and small size, and can be used as the terminal of computer to join the modern information network. Therefore, digital TV will eventually replace analog TV, which is the inevitable trend of TV technology development.

Extended data:

Daily maintenance of TV:

If the TV is used improperly, it will affect the life of the TV.

Pay attention to the influence of geomagnetism. The fluorescent screen of a large-screen color TV should be placed facing south or north, so that the direction of the earth's magnetic field is consistent with the direction of the electron beam rays in the picture tube, so as to prevent the earth's magnetic field from affecting the color purity.

Pay attention to ventilation and heat dissipation. When using large-screen color TV, don't cover it with plastic sheets or cloth covers. And don't pad foam plastic at the bottom, so as not to affect the ventilation and heat dissipation of color TV.

Pay attention to color and volume. The color, volume and contrast of large-screen color TV should be appropriate, which will not only have a good viewing effect, but also save electricity and prolong the life of TV.

Don't make the TV too bright. On the premise of clear image, it is best to dim the brightness. If the brightness is too high, it will first accelerate the aging of fluorescent substances in the TV set, make them run out prematurely and shorten the life of the TV set; Second, it will increase power consumption, cause waste, stimulate eyes and weaken vision.

Pay attention to protect the picture tube. Don't move and shake the TV when watching the program and just turning it off, so as not to damage the picture tube. Picture tubes should avoid direct sunlight.