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Ultra high frequency
Ultra high frequency (UHF) radio frequencies are those between 300 MHz and 3.0 GHz, which is higher than those of very high frequency (VHF). UHF and VHF are the most common frequency bands for television.
In Britain, UHF television began with the launch of BBC TWO in 1964. BBC ONE and ITV soon followed, and colour was introduced on UHF only in 1967 - 1969. Today all British terrestrial television channels (both analog and digital) are on UHF.
UHF frequencies have higher attenuation from atmospheric moisture and benefit less from 'bounce', or the reflection of signals off the ionosphere back to earth, when compared to VHF frequencies. The frequencies of 300-3000 MHz are always at least an order of magnitude above the MUF (Maximum Useable Frequency). The MUF for most of the earth is generally between 25-35 MHz. Higher frequencies also benefit less from ground mode transmission. However, the short wavelengths of UHF frequencies allow compact receiving antennas with narrow elements; many people consider them less ugly than VHF-receiving models.
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