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UHF versus VHF
There are two major formats for two-way radios. They are Ultra High
Frequency (UHF) radio and Very High Frequency (VHF) radio. Neither frequency
band is inherently better than the other. Both formats are effective ways to
communicate with another person so the right radio depends on the application.
The wavelength of a UHF and VHF signal plays a big role in which radio
technology to use. UHF has a shorter wavelength which makes it easier for the
signal to find its way through rugged terrain or the inside of a building. The
longer wavelength of VHF means it can transmit further under ideal conditions. [14]
For most applications, lower radio frequencies are better for longer range. A
broadcasting TV station illustrates this. A typical VHF station operates at
about 100,000 watts and has a coverage radius range of about 60 miles. A UHF
station with a 60-mile coverage radius requires transmitting at 3,000,000
watts.
If an application requires working mostly outdoors, a VHF radio is probably
the best choice, especially if a base station radio indoors is used and an
external antenna is added. The higher the antenna is placed, the further the
radio can transmit and receive. One exception to using a VHF radio outdoors is
if it is used it in a heavily wooded or rugged area. Under these conditions a
UHF radio may be able to transmit better though the terrain (unless the VHF
antenna is raised above the terrain).
If the radios are used mainly inside buildings, then UHF is likely the best
solution since its shorter wavelength travels through the building better.
There are also repeaters that can be installed that relay a UHF signal to
increase the communication distance.
There are more available channels with UHF so in more populated areas UHF
may be less likely to have interference from other systems. Since the range of
UHF is also not as far as VHF under most conditions, there is less chance of
distant radios interfering with the signal.
All UHF radios require a license, except for those operating in the Family Radio Service. Most VHF frequencies
except for MURS also require a license.
