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广大农村离电视发射台和电视差转台较远,地形复杂且电视信号极弱,外界干扰大,随着电视台数目的增多和电视机拥有量的扩大,提高电视机的收看效果是人们普遍关心的问题。只用室内天线就根本收不到,就是一般的室外天线效果也不好。这里作者根据多年的实践经验对提高电视机收看效果的问题做一介绍。 一、基本天线的制做 电视天线种类很多,有折合振子天线和半波振子天线;有单频道天线和宽频道天线。边远地区一般都用单频道天线,这种天线增益高,选择性好,有一个最大接收方向,如图为五单元折合振子天线。单元数越多,
The vast rural areas are far away from the TV transmitting stations and the television transmission turntables. The terrain is complex and the television signals are very weak and interfere with the outside world. With the increase of the number of television stations and the expansion of the number of television sets, improving the watching effect of the television sets is a common concern problem. Only indoor antenna can not receive, that is, the general outdoor antenna effect is not good. Here the author based on years of practical experience to improve the TV viewing effect to make an introduction. First, the basic antenna system Many types of television antennas, there are equivalent to the dipole antenna and half-wave oscillator antenna; a single-channel antenna and wide-channel antenna. Remote areas generally use single-channel antenna, this antenna high gain, good selectivity, there is a maximum receiving direction, as shown in the figure for the five elements of the dipole antenna. The more cells,