How Does a Television Work?

A television is a device that uses electronic technology to transmit moving image pictures and audio signals according to the visual persistence characteristics and visual psychology of the human eye, namely a television receiver. It is also an important broadcast and video communication tool. The basic system of a television is composed of three parts: camera, transmission and display. ^[1-2]

TV set mainly consists of

The first television came out in 1925.

1. Classified by main device used

(1) Tube television. The main circuit of this type of TV consists of 18 ~ 20

1. Front, rear and remote of the whole machine

Because the TV's on, off, program selection, volume adjustment, and various function settings can be completed with the remote control, the remote control becomes an essential peripheral part of the TV. With fewer and fewer control keys on the front panel of the TV, only the power switch is essential, because only when the power switch is turned on, the TV can enter the standby state, and the remote control can control the TV. When operating the remote control, the remote control must be pointed at the "infrared receiving window" on the front panel, and various control information is transmitted to the TV through infrared.

There are power cords, lead-in holes for receiving antennas, and video and audio input terminals on the back cover of the case.

2. The main components of the TV

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 the conventional maintenance work, the front panel and the middle frame do not have to be disassembled, and only the rear cover needs to be removed to perform general maintenance operations. Therefore, the front panel and the middle frame of a part of the TV set are made into a whole. After removing the back cover, you can see the main components in the TV. They can be divided into three parts: the back cover of the chassis, the front panel, the middle frame, and the picture tube, etc., and the main printed board (movement) and various components. ^[2]

If the TV is not used properly, it will affect the life of the TV.

Pay attention to the influence of geomagnetism. The phosphor 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 to prevent the geomagnetism from affecting the color purity.

Pay attention to ventilation and heat dissipation. When using a large-screen color TV, do not cover the plastic cloth, cloth cover, etc., and do not pad the bottom with foam plastic, so as not to affect the ventilation and heat dissipation of the color TV.

Pay attention to color and volume. The color, volume, and contrast of large-screen TVs must be appropriate, so that not only the viewing effect is good, but the power is also saved, and the life of the TV can be extended.

The brightness of the TV should not be too large. Under the premise of clear images, it is better to adjust the brightness to be darker. If you turn on the brightness too much, it will accelerate the aging of the TV s fluorescent substances, causing it to run out prematurely, and shorten the TV s life; .

Take care to protect the picture tube. Do not move or shake the TV when watching programs and just turning it off to prevent damage to the picture tube. The picture tube should be protected from direct sunlight. ^[4]