Many people have heard the terms UHF and VHF applied in a number of situations involving electronic communications. Both terms are used to refer to different types of frequencies that have been and are still utilized in radio, television and even cell phone transmissions. One of the key differences between UHF and VHF is that while both frequencies are part of the overall electromagnetic spectrum, they are two distinct frequency bands along that spectrum.
UHF, or ultra high frequency, relates to the band that covers the range between 300 megahertz or MHz and 3000MHz. VHF, or very high frequency, operates at a lower level, covering the frequency range from 30 MHz to 300MHz. Both UHF and VHF have been used over the years for radio and television transmissions, with individual stations assigned specific broadcast ranges along the bands. Government agencies normally determine what portion of each band is made available to broadcasters in any given area of a nation.
UHF and VHF have each been utilized in specific communication situations. For example, VHF is normally the band of choice for FM radio transmissions, while UHF has often been the band of choice for use in over the air television broadcasts. In contrast, the upper range of the UHF band is often utilized for ham radio operations. As with commercial radio and television broadcasting, government agencies determine the range or frequencies that ham radio operators within a given nation may legally use for their communications.
In terms of cell phones, UHF provides the band or frequency for mobile equipment that utilizes analog signals for communication purposes. Both UHF and VHF are still used in portions of the world where analog televisions signals are in common use. In addition, VHF is commonly used for civil aviation as well as public service announcements within communities.
UHF and VHF are only two of the several types of frequencies used along the electromagnetic spectrum. VLF, or very low frequency, includes any audio transmission under 30kHz, while LF, or low frequency, ranges from 30 to 300kHz. MF, or medium frequency, ranges from 300kHz to 3MHz and is often used for AM radio broadcasts. HF or high frequency ranges from 3MHz to 30MHz and is often used in short wave applications. The frequency range above UHF is usually know as SHF, or super high frequency, and is often restricted to government and military use only in a number of nations.