As a new generation of digital video audio interface, HDMI has become the basic configuration of LCD TVs. According to data provided by Silicon Image, the use of HDMI will reach 100 million by 2007, and by the end of 2008, HDMI 1.3 version had been popularized. In 2016, the HDMI version has been upgraded to 2.0.
With the popularization of the HDMI interface, there will be some new problems in use, especially many small details that cannot be ignored. Without careful attention, many unnecessary troubles will occur in use. The following is a brief introduction to the attention to the implementation of the HDMI connected LCD TV.
HDMI cannot be hot-plugged
One of the biggest advantages of the HDMI interface is that it is easy to use. As long as one cable, audio and video can be transmitted. And the interface is designed to be very easy to plug in and plug out without pressing any buttons. But this brings another problem. If it is directly plugged in or unplugged in the power-on state, it is easy to cause the chip of the HDMI interface to be burned. Therefore, when plugging and unplugging the HDMI cable, do not hot plug it. You must turn off the TV and HD player before you plug it in.
Version 1.1 HDMI interface can also transmit 1080P signals
There has been a misunderstanding for a long time that only HDMI interfaces with version 1.2 or higher can transmit 1080P signals. In fact, the 1.1 version of the HDMI interface can also transmit 1080P signals.
The author participated in a large-scale evaluation activity a few days ago, and also confirmed this problem during the evaluation process. During the event, the HDMI output of the PS3 was set to 1080P, and it was found that many LCD TVs with HDMI 1.1 interface could not display normally, and there was no signal on the screen. But when connected to Skyworth 47L20HF, it can be displayed. After contacting Skyworth technicians, it is confirmed that the HDMI interface of Skyworth LCD TV is version 1.1 and can transmit 1080P signals.
The 1.1 version interface only says that it can theoretically transmit 1080P signals. Specific to each machine, whether it can be transmitted depends entirely on the design of the manufacturer. Most 1.1 version interfaces cannot be transmitted. In fact, under the HDMI interface, as long as the TV's circuit is good enough, 1.1P transmission 1080P can achieve the same effect.
Short-distance transmission of HDMI cable can be
For most users, the high-definition player is placed next to the LCD TV. The required HDMI cable is no more than 2 meters, and a short 1 meter is sufficient. Generally, a 1.5 meter HDMI cable is sufficient.
Cables below 5 meters are considered to be short-distance transmission. The selection of HDMI cables is relatively simple. An important factor affecting the quality of the cables is the thickness of the conductors. For HDMI cables, they can be divided into 24, 26, 28, and 30 types. The smaller the number, the thicker the wire diameter, and the better the effect. For the lines below 5 meters, choose the 28 and 30 lines, 1.5 meters is not more than 80 yuan is appropriate, 5 meters is not more than 150 yuan.
Long distance transmission has strict requirements on the wire
For long-distance transmission, the requirements for HDMI cables are very strict. In addition to the thickness of the wire diameter, the factors that determine the quality of the HDMI cable are as follows:
1. Selection of raw materials. For good wire, the core wire is silver-plated, and the low-priced rotten wire is tin-plated.
2. Production process. The insulation foam of the outer layer of the wire is closely related to the transmission quality. The low-grade foam production equipment only needs 100,000 yuan, and the high-end equipment is as high as 16 million yuan. The quality difference is very different.
3. Shielding effect. The shielding effect of HDMI cables produced by low-end equipment is only 80-85%, while the shielding efficiency of high-end cables reaches 95%.
Long-distance transmission. When transmitting 1080i or 720P signals, the difference is not great, but when transmitting 1080P signals, the requirements for the wire are very strict. If the quality of the wire is not high enough, screen jumps may occur in light, large red spots may occur, and no signal in heavy .
Therefore, the selection of long distance lines must be very careful. When you choose, you ca n’t just look at the outer thickness of the line. Many of the lines that look very thick, but the outer skin is thick. In fact, they are all 28 lines. They cannot transmit 1080P signals at all. For HDMI cables of more than 10 meters to transmit 1080P signals, it is best to use line 24, and at least to ensure line 26. Line 24, transmitting 1080P signals, can reach 10 meters. And the 28th line transmits 1080P signals, even at a distance of 10 meters, the quality cannot be guaranteed, and the HDMI extender can be selected strictly.
HDMI wiring carefully buried in the wall
Many netizens like to bury the HDMI cable in the wall in advance during decoration. We think that we must be cautious, and avoid it as much as possible unless it is a projector.
If you want to use a computer to drag two, surf the Internet in the study, and watch high-definition in the living room, we think that laying HDMI cables in advance will have a lot of troubles, such as embedded cables. If you purchase 28 and 30 cables, you will definitely be able to transmit 1080P programs. There are endless problems to encounter. At present, most netizens do not use real 1080P signals to test the quality of HDMI cables. When they really use 1080P signals in the future, they find that they cannot transmit, and they are late. In addition, the HDMI cable can only transmit image and sound signals, and cannot transmit signals such as mouse and keyboard. The nominal 10-meter wireless keyboard and mouse are generally 4-5 meters away when used in a home environment. Therefore, directly lay the HDMI cable to connect the computer and the TV. Within a distance of about 4 meters, it can be considered that beyond 5 meters, another signal extender such as a mouse and keyboard is required.