UB317Z (BC350C) 0916 9/16/03 12:42 PM Page 4
What is Trunk Tracking?
Conventional scanning is a simple concept. You enter a radio frequency in your scanner’s memory which is used by someone you want to monitor. For example, the police in your area may transmit on 460.500 MHz, the fire department on 154.445 MHz, the highway department on 37.900 MHz, etc. So when your scanner stops on a frequency, you usually know who it is, and more importantly, you can stop on a channel and listen to an entire conversation. This type of scanning is easy and fun.
As the demand for public communications has increased, many public radio users don't have enough frequencies to meet their needs, and this has created a serious problem.
Trunking radio systems have been implemented to solve this problem.
In a trunked radio system the frequencies are shared among the police and fire departments and a computer systematically assigns available frequencies when they are needed for communications.
Sharing of the available public service frequencies, or trunking, allows cities, counties, or other agencies to accommodate hundreds of users with relatively few frequencies. Following a conversation on a trunked system using a convertional scanner is difficult, if not impossible. Because when there's a short break during the conversation you're monitoring, a completely different frequency will be assigned within the trunked system when the conversation resumes.
If your local police, fire, and EMS agencies use a trunked system and you want to be able to follow their communications, you will want to purchase one of Uniden’s Trunk Tracking Scanners.
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