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解决远距离居民区接收困难的早期尝试有几种方案,即,在一些良好的位置上获得高质量的电视信号。这种接收位置现在被称作为“前端”。在这种位置上,经常利用一个有适当高度的铁塔来提供所需的高质量信号,在这种铁塔上装有高增益、高方向性、并指向电视发射天线的接收天线。有时,也可选用把木桅杆设置在山顶上的方法,有大桅杆上装上指向性的接收天线。接收天线越高,信号电平就越高,一直到
There are several options for early attempts to solve reception difficulties in remote neighborhoods, ie to obtain high-quality television signals in some good locations. This receiving location is now called the “front end”. In this position, it is common to use a tower of suitable height to provide the desired high quality signal on which the tower is loaded with a receiving antenna of high gain, high directivity and directed toward the transmitting antenna of the television. Sometimes, the method of setting the wooden mast on the top of the mountain is also available. The main mast is equipped with a directional receiving antenna. The higher the receive antenna, the higher the signal level up to