The difference between the UHF band and the VHF band
on August 19,2023.
1. VHF (144.00 ~ 148.00MHz) This is the typical VHF band, which is a very active local mobile communication band. The ionosphere of this frequency band signal basically does not produce reflection, the radio wave is mainly transmitted by direct wave line-of-sight, the transmission encountered a large building or mountain, will produce reflected waves, therefore, can only be used as a two way radio close-range communication. This band of antennas is the highest amateur radio production rate, there are a variety of high-gain directional and omnidirectional antennas, there are car mobile whip antennas and small handheld antenna and so on. The interference in VHF mainly comes from cordless phones, BP sets and other base stations. This frequency band is the dedicated frequency band of our HAM, while UHF is the common frequency band. 2. UHF (430.00 ~ 440.00MHz) It belongs to the UHF band, and the direct wave propagation is worse than that of the VHF, and the penetration of the UHF is better than that of the VHF, so there are more UHF in cities with high-rise buildings. But at the same time, the attenuation of the air is larger than that of the VHF, which is not suitable for long-distance communication. When using longer cables, the attenuation of the cable to the signal should be considered. Due to the high frequency of this frequency band, the noise is small, and the manufacturers compete to launch a number of small and fully functional frequency band antennas can be relatively small, and can be set on the car navigator, therefore, this frequency band mobile communication is very active. In order to solve the problem of close communication distance, many amateur radio operators set the relay platform at a high altitude, with the help of forwarding differential signals, can greatly increase the communication range, as long as the enthusiasts use a small power and simple antenna, they can and distant radio QSO. In the summer and other seasons of unstable weather, radio waves refracted back and forth between the three layers of the atmosphere, and the attenuation is very small to the distance. There are also phenomena such as meteor trail reflection and tropospheric scattering, which will also make the radio waves in this frequency band propagate beyond the visual range. VHF and UHF are the most interesting, useful and challenging bands for amateur radio operators, so they are currently used by amateur radio operators in a wide variety of situations. Many people love the convenient way to communicate on the VHF/UHF band. It makes local communication between enthusiasts and friends very convenient, whether at home or in the car, or while traveling or working. There are also some people keen on long-distance communication, long-distance communication and local communication in the dissemination of a big difference. In addition, satellites are often used to communicate over thousands of kilometers. Many hobbyists like to make their own devices, which have a...
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