Radio interference factor
Medium wave The propagation of medium wave is mainly affected by the ionosphere. The medium wave station received at night will be more than during the day. This is due to the different changes in the conductivity of the ionosphere during the day and night. During the daytime, due to sunlight, the density of the ionosphere increases, the conductivity is enhanced, and the absorption of electric waves is also large. A large part of the medium wave is absorbed and spreads not far; at night, the atmosphere is not exposed to the sun, and the ionosphere has a large conductivity. If it is weakened, the medium wave can be transmitted to a long distance through the sky wave path. Therefore, it is best to listen to the medium wave station at night. Short-wavelength mid-wave broadcasting receives from the transmitting antenna of the radio to the radio. The distance is usually within a few hundred kilometers in diameter, and the medium-wavelength wavelength is relatively long, which is not easily affected by obstacles such as buildings. The distance from the short-wave transmitting station to the receiver is often thousands of kilometers or even tens of thousands of kilometers. The transmitting antenna of the radio station also has a certain direction and elevation angle, which is easily affected by the atmosphere and the obstacle during the propagation process. If the place where you live is a steel-reinforced building or a high-rise building, the broadcast signal is shielded from the part, and the indoor signal is much weaker than the outdoor. Therefore, the best way to listen to the short-wave is to listen to the radio rod antenna outside. Use the radio when outdoors, or near a window, or use an outdoor antenna to improve reception. Frequency Modulation Powerful VHF TV broadcasts and radio waves from the BB transmitter will interfere with FM reception. In addition, several FM stations with adjacent frequencies and strong transmit power will also interfere with each other. Therefore, when receiving a strong interference signal, shorten the rod antenna, change the antenna direction, change the listening position, and minimize the interference level. In addition, televisions, fluorescent lamps, thyristor dimming lamps, computers, car engines, electric motors and other electrical equipment and other signal transmitters will also cause some interference to the radio signal reception. When using the radio, please contact the above equipment. Keep a certain distance. Do not use an external antenna during thunderstorms!
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