Luohe where the campus radio quotes Henan Jiaming Yang 1503 +71780 +75 www.69139139.com 1399 +229 +631 Unit 2, Building 208, Cheng * City Market Milan sun the common campus radio transmission mode: audio cable set pressure ( given resistance) transmission, wireless FM transmission, cable FM transmission in three ways. ① The most common is the the cable constant pressure audio twisted pair transmission: The advantage is terminal cheap, simple structure; drawback is that each classroom are required wiring, the system is configured in strict accordance with the principle of power matching and impedance matching, scalability, can not stereo broadcast program capacity is small (only a set of programs) that can be transmitted, broadcast different content at the same time can not be done by grade. ② wireless FM transmission: The advantage is the simple construction, no wiring, low price, can achieve multi-channel broadcast; disadvantage is the need to take up space frequency resources, frequency needs to be approved by the radio management departments in principle, susceptible to outside interference, reliability relatively poor. The ③ cable coaxial of cable FM transmission mode: wired FM frequency division multiplexing transmission work of cable based on the cable TV coaxial advantage can achieve multiple simultaneous transmission (W Series 100 channel receiver) can strong expansion, the terminal speaker as long as the receiving level can be unlimited number, the power limit. Cable technology in China has gone through nearly 20 years of development history, has fully matured, inexpensive accessory products, stable performance. The the wired FM radio and closed-circuit VOD, dual control, CCTV Total cable transmission, no wiring, construction is simple, scalable transport number of programs can achieve the intelligent broadcast addressable control functions; drawback is wired FM transmission mode is based on the weak signal transmission work, FM Speaker with external 220V AC power, but the schools in the classroom can provide a stable 220V AC power. The several technical and general schools should be used in the cable FM transmission mode wired FM radio scalability, high performance and low cost, and with closed-circuit double control, VOD, teaching, campus multimedia "multi-play". Jiaming Yang 1503 +71780 +75 www.69139139.com 1399 +229 +631 Milan sun, Zheng * City Market Building 5, Unit 2, 208