Very High Frequency or VHF radios operate in the frequency range of 30MHz to 300MHz.
Ultra High Frequency or UHF radios operate in the frequency range of 300Mhz to 3Ghz.
VHF and UHF radios are widely used by public service agencies for two-way radio communication. Modern VHF and UHF radios support both analogue and digital transmission methods.
The point to point transmission and reception of VHF and UHF radio signals makes them ideal for short-distance terrestrial communication.
A typical VHF or UHF radio only has a range of a few Km but can be extended up to 80 Km by the use of repeaters The range can be affected by many variables. Atmospheric and physical obstructions such as mountains and buildings, and time of day will all have an effect on the signal transmission and degradation of signal reception.
Codan Automated Link Management (CALM) is a new and very advanced feature in which the transceiver performs the channel selection operation automatically. The handset in most ways looks and operates like a mobile phone.