同轴电缆接口的安装方法
Installation method of coaxial cable interface
同轴电缆接口的安装方法如下:
The following installation method of coaxial cable interface:
(1)细缆 将细缆切断,两头装上BNC头,然后接在T型连接器两端。
(1) thin will thinnet is cut off, two mounted on the head of the BNC, then in T type connectors at both ends.
(2)粗缆 粗缆一般采用一种类似夹板的Tap装置进行安装,它利用Tap上的引导针穿透电缆的绝缘层,直接与导体相连。电缆两端头设有终端器,以削弱信号的反射作用。
(2) thick cable hawser generally use a Tap device as splints for installation, insulation layer using the guide needle Tap on the penetration of cable, conductor connected directly with the. Both ends of the cable head is provided with a terminal device, in order to weaken the effect of the reflected signal.
二、参数指标
Two, the index parameters
1、主要电气参数
1, the main electrical parameters
(1)同轴电缆的特性阻抗 同轴电缆的平均特性阻抗为50±2Ω,沿单根同轴电缆的阻抗的周期性变化为正弦波,中心平均值±3Ω,其长度小于2米。
(1) the average characteristic impedance of coaxial cable characteristic impedance of coaxial cable is 50 + 2 Omega impedance, periodic change along a single coaxial cable as the sine wave, the center average value + 3 Omega, its length is less than 2 meters.
(2)同轴电缆的衰减 一般指500米长的电缆段的衰减值。当用10MHz的正弦波进行测量时,它的值不超过8.5db(17db/公里);而用5MHz的正弦波进行测量时,它的值不超过6.0db(12db/公里)。
(2) the attenuation of the coaxial cable generally refers to the attenuation value of cable section of 500 meters long. When using the 10MHz sine wave was measured, its value does not exceed 8.5db (17db/ km); and the use of 5MHz sine wave was measured, its value does not exceed 6.0db (12db/ km).
(3)同轴电缆的传播速度 需要的最低传播速度为0.77C(C为光速)。
(3) the lowest propagation velocity of coaxial cable transmission speed required is 0.77C (C is the speed of light).
(4)同轴电缆直流回路电阻 电缆的中心导体的电阻与屏蔽层的电阻之和不超过10毫欧/米(在20℃下测量)。
(4) the resistance center conductor of a coaxial cable DC loop resistance cable and shielding layer resistance and no more than 10 milliohms / M (measured at 20 DEG C).
