Advantages and Disadvantages of Five Lines to Videoconferencing Systems

The development of the Internet has made people more and more aware of the Internet and has become more and more extensive. At present, all kinds of electronic products are seeking an informational road. Then the five types of wires that are widely used in computer networks are indispensable for the connection of products. In AV network cabling, it also seems to be a trend. We can see that various audio and video products are developing in this area. From intelligent projectors to digital conference systems, central control systems, matrixes and switchers, five-category networks are used as the direction for the development of new products. The series of questions raised by this has been discussed with dealer friends for a long time. Below, we use the conference system as an example to look at a few questions: 1. Is it possible to use the connection method to distinguish between all digital conference systems? Five-category connection is an all-digital system? The original professional cable connection is an analog system? What are the advantages of the Category 2 and 5 lines? 3. Has the professional cable that has been used for many years been introduced to the market? First of all, whether it is a five-wire connection or an original professional cable connection, it is just a connection method. Both can transmit digital signals. Therefore, we cannot use connection methods to determine whether it is a digital conference system or an analog conference system. The five-category wire connection method is widely used, and there is nothing wrong with its advantages.

The quintuple, also known as twisted pair, is now the most common transmission medium. It consists of two mutually insulated copper wires, typically 1 mm in diameter. The two wires are twisted together to prevent their electromagnetic induction from interfering signals in adjacent pairs. The current twisted pair cable generally contains 4 twisted pair pairs. Twisted pair can be divided into shielded twisted pair (STP) and unshielded twisted pair (UTP) according to whether it is added with the shield of the metal mesh sheath. The general computer local network only uses unshielded twisted pair (UTP). If the data volume is large, it is best to use shielded twisted pair (STP). The network type five wire connector is generally RJ-45 crystal head; the maximum effective transmission distance is 100m from the hub. If you want to increase the transmission distance, repeaters can be installed between two twisted pairs, and up to 4 repeaters can be installed. If four repeaters are installed to connect five network segments, the maximum transmission distance can reach 500m. The quintic line frequency bandwidth is 100 MHz. The frequency bandwidth (MHz) is different from the data transmission rate (Mbps) of the cable. Mbps measures the number of bits transmitted by the line per unit of time, and MHz measures the number of oscillations of electrical signals in the line per unit time. Twisted pair can be applied at most to CMSA/CD (Carrier Sense Multiple Access/Collision Detection) technologies, namely 10BASE-T (10Mbps) and 100BASE-T (100Mbps) Ethernet (Ethernet) in. The quintessential line has not yet been adopted by all conference system manufacturers (including some internationally renowned brands), but it also has some deficiencies in its application in this area.

As we all know, the current transmission in computer Ethernet is very weak, and most of it is data traffic. According to IEEE 802.3af regulations, power is transmitted via Ethernet, and the power transmitted to each node is limited to 350 mA. At present, the conference system on the market is passive, and the power supply and data transmission are transmitted in one cable. The power of the conference system is generally 100W-200W, and the power supply voltage is 24V-48V. Then the transmission current is about 2A-8A. Far greater than the IEEE802.3af regulations. Therefore, this is a security risk. In particular, the RJ45 plug is used as a Category 5 connector, and the contact between them is very weak. Large currents can easily cause joint damage. In the connection, it is important to consider the solid reliability of the connection line. The RJ45 module interface connection between the RJ45 crystal head and the conference unit is only based on the small bayonet attached to the RJ45 port. The people who use the computer network are very clear that such connection is very weak, but on the computer network, a little loose or temporary loss is not injurious.