What Frequency Band Suits My Location? Choosing Between VHF or UHF Frequencies
It’s good practice to remember that the location of your event is very important to the frequency range (VHF or UHF) of the hire radios you require!
Planning an indoor event?
Ultra High Frequency (UHF) offers the best penetration versus man-made structures. The narrow wavelength finds it much easier to transverse concrete, brick and wiring than Very High Frequency (VHF). This increase in penetration comes at a price as the signal will not carry as far.
UHF radios are better suited for built up areas and they are very popular in cities. This increases the likelihood of radio systems being used in close proximity and potentially operating on the same frequencies. As a result UHF band radios are limited to a maximum power of 4 watts to minimise this.
As far as communication range would be concerned, you should be able to cover several hundred meters. This of course is entirely dependant on location. If the location contains substantially thick walls, elevator shafts or a lot of electrical cabling then the reception will be reduced. Potentially to tens of meters. Largely, this can be overcome by the use of a Radio Repeater which can boost the signal (depending on licence limitations) from 10 watts to 40 watts.
Planning an outdoor event, VHF or UHF?
Very High Frequency (VHF) comes into its own here. The wavelength of VHF is longer than UHF and as a result carries further. This is further boosted as VHF band radios are permitted to use 5 watts as supposed to UHF 4 watts limit.
In a country or park location with minimal structures blocking line-of-sight between the two users a distance of several miles can be achieved. This can be further increased by utilising a Radio Repeater system and desktop or in-car mobile radios. With a repeater mast at an elevated location and the signal boosted (depending on licence limitations) by 10 watts to 40 watts. This can greatly increase the area of coverage. Still, black-spots are to be expected in areas that dip out of line-of-sight or substantial structures block the signals path.
We will choose a frequency band best suited to your location. Should your event be large or require Repeaters then we would likely recommend a Site Test to identify the most suitable solution. This is especially important where communications are critical for human safety. A site test will identify the equipment required, the most suitable location if a Radio Repeater is needed and identify any black-spots.
What’s a Repeater?
A Repeaters is used to boost a radio signal so that a larger area is covered. The Repeater receives your transmission on one frequency, amplifies it from 4 – 5 watts to 10 – 40 watts (depending on licencing limitations) and rebroadcasts it on a different frequency.
Depending on the range and site shape you wish to cover, various size Antennas from small clip-mount whips to large folded-dipole tripod erected masts are available.
For more more information on our radio hire services please contact us on 0800 369 9123