Various broadcasting systems are shallow
Public broadcasting system is widely used in daily life, especially in enterprises, schools, government agencies and other departments. However, the public broadcasting system that seems to be inconspicuous, after careful analysis, still has a lot of knowledge. The first thing we need to do is to identify several public broadcasting systems and analyze their characteristics. In order to be 'targeted' and improve their knowledge, they can also provide a lot of reference for their purchase and use. At present, public broadcasting systems can be divided into the following categories according to different transmission modes. I. Constant voltage Broadcasting System constant voltage broadcasting system refers to the broadcasting system in which the front end uses constant voltage broadcasting power amplifier to amplify the audio power of the sound source and transmit it to the speaker through wires. The most basic structure of such systems is: sound source-Power amplifier-Speaker. Depending on the functional requirements, the main control device can be added at the front end. The main function of the main controller is to control the input/output of the sound source, peripheral equipment (Such as power amplifier) Power Management, partition management of line output area, etc. I used Nanjing Wankai's MP3 music player and constant voltage partition broadcast host to feel good. Of course, such partition control must be based on the physical partition of the line. Its main features: high transmission stability, low failure rate, simple structure and convenient maintenance. Second, the FM broadcasting system refers to a public broadcasting system in which the front-end sound source is modulated by a modulation to transmit the radio frequency signal to the amplification point, and then the audio signal is untuned to perform power amplification locally. According to the different transmission carriers, it can also be divided into Wired FM broadcasting system and wireless FM broadcasting system. The basic structure of this type of broadcasting system is: sound source-Modulator-MoDem-Power amplifier-Speaker. Depending on the functional requirements, the main controller, peripheral equipment and multiple regulators and sound sources can also be added on this basis. The mode of operation of the FM broadcast master is that the control signal is modulated into a radio frequency signal and the modulated audio radio frequency signal of a single or multiple different frequencies is mixed by the mixer and transmitted to each individual sound point, in each separate of speaker point anti-modulation for control signal and audio signal analysis control command ( Whether this point works and which sound source to choose)After selecting the sound source, it is amplified and output by the power amplifier. I used Nanjing Wankai's control host, which integrates sound source modulation and data instruction modulation into one host. The principle is similar to what I said. Its main features: it can realize single cable or wireless transmission of multiple program sources and realize point-to-point control. The equipment is simple, easy to maintain, and extremely powerful for use in various places. However, the attenuation amplification of radio frequency signals should be considered in line transmission (Familiar with CATV is very simple). Three, network broadcasting system refers to the broadcasting system that transmits audio and control signals through local area network or wide area network. Its structure is: control software ( Or broadcast master with integrated control software and computer functions)-Internet-Network broadcast terminal. The basic function of the network broadcast terminal is to analyze whether this address bit responds to the action according to the front-end control command, and select a sound source to amplify the power to the speaker. With the popularization and development of network technology, the existing network broadcasting uses TCP/IP protocol to realize two-way intercom, remote paging and other functions. The characteristics of this type of broadcasting system: multi-purpose in the first line, making full use of IP network resources; More program source point-to-point of real-time play; Two-way intercom, remote paging. This article mainly explains the definition, structure and main characteristics of the three public broadcasting systems. I hope that it will be helpful for everyone to purchase and use the public broadcasting system.