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How Public Broadcasting System Selection

2014/7/26 14:47:24

 

n the broadcasting system construction process, people tend to focus on the relevant equipment supporting the above, while ignoring the broadcast transmission cable choice. In fact, it works for a broadcasting system, to obtain a satisfactory sound, in addition to broadcasting equipment should be equipped with a high quality (power amplifiers, speakers, etc.), the cable broadcasting transmission quality to some extent also affect the sound quality.

       Currently, the broadcasting system construction process, people tend to follow home audio systems use "speaker wire" mode, the selection of a broadcast transmission cable system. In fact, there exist certain errors.

       Home audio systems use "speaker wire" as the difference between positive and negative polarity and wrapped in transparent plastic dyed copper, gold, silver two colors, our study is called, commonly known as "gold and silver" in the market. "Gold and silver" is based on the number of standard copper wire inside the parcel to be, classification becomes how much "class", not very standardized.

      "Speaker wire" is mainly used in home audio systems, using only the length of 3-5 meters under normal circumstances, and therefore should try to select the option "rough" that "material" a little better "speaker wire" in order to improve the signal the transmission rate and reducing transmission losses.

       If the "speaker wire" for public broadcasting system, as laid long lines, the project cost can not determine the choice of high-level "speaker wire", use only low-level "speaker wire." And this kind of "speaker wire", the quality is relatively poor, mostly by a number of small factories (workshop) using relatively backward production process, the user can not be assessed by reference to national standards of acceptance.

        Downscale "speaker wire" in general are parallel lines, namely transparent plastic strand copper wire wrapped around two parallel arrangement. Electromagnetic principle tells us that there is a parasitic capacitance between the line between any two parallel lines, and the parasitic capacitance between the signal transmission line will cause the bypass high frequency component, the longer the line, the greater the influence of parasitic capacitance between lines . Thus, long-distance transmission of broadcast signals, inappropriate choice of parallel lines, or likely to cause treble is not clear, nausea and other phenomena.

       Scientists have discovered ways to effectively overcome Twisted influence of parasitic capacitance between lines, and thus the way in computer networks using twisted-pair cable, premium sound can be widely used in wire. With the popularity of twisted-pair cable manufacturing process of the way, more and more use of twisted-pair cable transmission mode. Therefore, the public broadcasting system is also long-distance transmission of broadcast signals should use twisted-pair cable broadcasts.